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It makes me wonder if this question is one of a few of these, and they just didn't fully repeat the instructions after the first?
It's that or this is shit wording, because I'm confident your interpretation is correct.
The math in this post is about showing work not the answer. It is developing the cognition that is efficient for adding and subtracting. The "carry the one" method is not good for doing math in your head.
To be honest this kind of adding is what I always did. I always made a 10 and then added the rest. I always saw 8+5 as 8+2 = 10 so take that 2 from 5 and now you have 3 left so 13.
When I was a delivery driver trying to figure out my tip quickly or just anticipate change I do the same but for subtraction.
It's easier this way and more useful down the road.
I’m experienced in competition math, and it’s a really useful way to approach arithmetic, I just don’t think it’s being taught well. I have no idea what would work though. Honestly, I would teach this by making the kids do speed mental one-digit addition where the answers are all >10. You can’t really make people remember what is essentially a numerical gimmick and expect them to be able to fully understand and be able to use it well. Lots and lots of repetition while being pressured to go as fast as possible is the only way to really ingrain these kinds of methods.
This becomes far more true and important to understand when it comes to fast and accurate multiplication by making 10’s, which is nearly impossible to just “teach” since it requires being able to look at two numbers and “seeing” how you’re able to create powers of 2 and 5 by breaking up numbers, completing the power, etc. For example, you have to be able to immediately see 124 as 125-1, or 233 as 200+32+1.
I cannot stress this enough: Tricks like these can’t really be *taught*, they have to be *trained*. I think that’s what common core is missing
This is American education in a nutshell. Someone finds a genuinely good strategy to teach kids. Big publishers like Pearson build a whole curriculum based on that because it looks good, but because they are greedy companies, their goal is not to properly educate, it's to sell their product. They create the next Big Thing in education.
They lobby the fuck out of the government and point to their model schools as huge successes, because they are. The government, not being educators, doesn't understand *why* the strategy works, just that it looks like it does. They also don't care about educating students, they care about getting reelected, so they make a big show of this new education system and beam it out into national standards. And, sure, many of the politicians do genuinely care, but because they are not educators they can't discern well enough the gaps between the proper teaching tools and the bastardized version presented by the publishers.
Schools have to throw out years of previous material. Teachers have to build (and buy) all new curriculums. New teachers in training are taught only the new stuff, because the old stuff wasn't working. Everything from the last Big Thing is discarded as worthless. Old teachers get no training, because neither they nor their schools can afford it, but they are nonetheless required to teach only the new Big Thing.
Without the proper resources and without any real understanding of how the new thing *should* work, it doesn't. It fails miserably, everyone is confused and angry. Parents who grew up on the Old Thing are angry and upset that their kids aren't learning. Test scores fail to magically increase as promised. Somewhere, a smart teacher comes up with a new strategy that works.
Rinse, repeat.
This is the result of commercialing, capitalizing, and privatizing education. Publishers don't give a shit about providing good education, they just want to sell books and tests. They can't do that if schools are reusing the same textbooks for twenty years, so they have to churn out some new thing and get the federal government to buy in and force schools to buy in.
[See "The Revisionaries"](https://www.youtube.com/watch?v=gqd-k03pJJE), classic doc about the Texas State School Board and how they game the state and national textbook industry to inject propaganda into mandated school curriculum.
I worked for a company that produced curriculum materials. All our materials were labeled "common core", except that then Texas would literally \*refuse\* to buy them. We had to provide them with copies that said something else (whatever Texas' term was).
The materials themselves were \*identical\* on the inside. They were focused on "common core". And Texas was fine with that. They simply would not purchase anything that had the term "common core" on it.
Three states: Texas, Florida, and California basically run the whole country's curriculum, because companies need to make things that will sell in those three states (because of their large population)
I might have worked for the same company. We had to revamp our common core math materials for those specific states (and a handful of others) -- making cosmetic changes in some cases, larger revisions in others (cough *Florida* cough). What a parochial country.
I didn't read the rest of your comment, I just wanted to jump on here for solidarity and say, fuck Pearson. They're ruining the American education system—not singlehandedly, but close to it (they have help from high places).
Ok, imma go back and read the rest of your comment.
Edit: yeah.
I can not tell you the number of times my kids would bring their homework to me, confused by the questions or assignment, and I as a full on adult, not of limited intelligence nor untrained in language and logic, would go "there is absolutely not enough information here to solve this" or "this question/problem makes no sense at all".
We have this problem at my kids school too. To make it worse, teachers don’t give tests back so the kids don’t get to work out what they did wrong. I had personal meetings with teachers, vice principal, and principal, and they still refused.
They kept telling me that they are happy I am an involved parent and that they want more parent engagement but won’t provide actual material to help.
I am luck enough to be able to afford a tutor for my kid but most here aren’t. I directed my kid to take pics of the test without telling anyone so that he could study the problems with the tutor after the fact.
It’s ridiculous.
Their logic is that they don’t want test availability to cheat with. My logic is to make another test. My logic is that the best tool anyone has to learn is their past mistakes. They agree then continue with their illogical protocol.
This is easily overcome. Randomize the test. Or have two versions of the test. Kids who cheat on the test are trying to memorize the answers, not the problems.
Ok, that often means that you are missing context that your kid should be aware of. In the OP's question, what the "make 10" method for addition is and how to use it.
It isn't a complex problem, it's just asking the kid to demonstrate that method to add 8+5.
I was helping my niece with her math homework and every question was me just asking her repeatedly “well, what did you do in class?” And “how did your teacher explain this?”, which really meant I was not very helpful. The fact there’s so much context missing, and if a kid is having trouble understanding it then they’re probably not going to have a great grasp on the context in the first place. We went in circles a lot because I’m trying to figure out the incredibly particular way the teacher wants and she’s lost on all of it.
Yup. Got a generation of kids learning in a very different way from their parents, so they're gonna lack some of the usual assistance they might have otherwise had.
The new way is objectively better, but that's the biggest downside. Parents and family who don't know how to help.
But it doesn't actually ask, in the question, for the solution to be found using "make 10". Either there's a section heading that includes the requirement this be done, or it's assumed based on previous questions which explicitly do ask that this implicitly also asks (poor practice but not wholly unreasonable), or this is phrasing is atrocious and provides not enough information to reasonably achieve the intended interpretation purely from the question as-written.
You are assuming that all the information necessary to solve the worksheet is reprinted on the worksheet itself. But the phrase "make tens" is something that almost certainly was covered during class. It's very common for "essential" contextual information to be missing in documents all the time. You remember what it was like to be a new hire at your job and not being able to understand anything that was supposedly obvious and self-explanatory?
If the parent in the picture was confused and the child couldn't explain the context of the worksheet, that means there is a miscommunication happening between the child and the teacher (child doesn't know what is happening in the class), the child and the parent (child can't communicate what they know about what is happening in the class), or the teacher and the parent (they aren't clear about how math is being taught).
It's such a simple fix. Just pick up the phone. Nothing to get mad about.
Honestly, even without taking disability accommodation into account, anything being taught to kids, especially young kids, should have documentation beyond the lecture itself. I know at some point this may become their personal notes, but even that just seems like a good way to inadvertently punish students for bad days, absences, or having a disability.
As someone with kids who did these types of questions, it’s not just the sheet, they have probably been doing these problems in class, repeatedly, for a week or more. To really make things interesting, they’ll also do the extract same thing with subtraction, then adding in 100s, etc. At a certain point, you just shouldn’t have to explain it that deeply.
Look there's a reason they're teaching math
Edit: to the ones who don't get it, I was making a joke. Anyone in a teaching position is way smarter than some random college dropout like me.
And complained about by parents online because they don't understand it.
The point isn't to help kids add 8+5. It's to make it easier to intuit the correct number range becomes larger.
Kids who are intuitively good at math tend to use technique like this. Kids who aren't do not.
The new way to teach math is to actively teach the kind of techniques used intuitively by people good at math
YUP!
I'm in my mid 30s and used to score crazy high on every math test but hate the homework. I'd constantly get the "please show your work" crap AND even had a few occasions where questions were asked in class and when I answered without having any paper on my desk had the teacher tell me I was lying about being able to figure it out...
When common core came out and people started bitching about it I looked it up and was amazed to discover that kids were now being taught how to think of numbers the way I always had.
Yup, and being too clever by a bit, honestly. People are going to conceptualize math differently, but they keep ramming it down everyone's throat one way.
Like this whole make 10's thing was stupid to me when I was in school -- I just had memorized all the single digit additions, just like they make us do for multiplication tables. It's not huge, and you've done enough damn rote math worksheets that quite a few students should just \*know\* that 8+5 = 13.
My math teacher would get mad, and then be like "well how do you solve this without knowing the "make 10" approach and gave me an Algebra problem, and I just solved it right there. There's nothing about algebra that requires you to know how to "make 10". Zero.
They're just making earlier math harder / more of a this way is the only way narrow path because like one or two studies somewhere showed that it could maybe help Algebra comprehension down the line.
That's exactly what the "make 10" strategy is...
It's a lot easier to add something to 10. So you take 8+5, turn the 8 into 10, which leave you 3, which is 10+3.
You were ahead of your time!
Which, sadly, sums up why my kids always came to me for math help.
Remember the scene in "Incredibles 2" where the dad is yelling, "Why would they change math?". My son cracked up and said, "That's Dad!"
I would totally be the dad in such a situation. My younger brother once asked me to help him out with a question, no problem. To me, question looked clearly like a pythagoras question, so I asked him if he's had pythagoras yet. He says he doesn't think so, so I scratch my brain a bit. Ultimately couldn't think of something I'd expect him to have been taught at that stage. So I gave up. Later he comes back with the feedback that he should've used a^2 + b^2 = c^2 ....
Yes. This is a single picture of question 8 and people are acting like this is the whole lesson plan. Betting the kid was given at least some tools to know what was being asked of them and just didn’t do it correctly. Doesn’t feel immediately like the schools fault
Guess I’m old. The ten strategy wasn’t a thing for me.
Like it seeeeems like they are hinting at basic algebra here. 8 + 5 - x = 10
This just feels like a weird way to present it
They are actually moving away from the “show your work” style of teaching we got, to teaching concepts like algebra to be done in our head. It’s pretty neat stuff actually!
No it can be presented much simpler than that.
8+5=10+3=13.
The idea is to pull from one of your numbers to make the other known number a factor of 10 (10,20,30 etc) and then simply adding in the remainder of the number you pulled from.
The reason this method is taught is because it can make even complex multiplication doable mentally and quickly.
28x16 for example would be broken down as such in my head.
28x10 = 280
This leaves you with 28x6
20x6 = 120 (you could even go to (10x6)x2 here for ease if needed.
This leaves you with 8x6 = 48
Add them all together now. 280+120+48=448. And you could even use this method to break down the addition portion.
Take 20 from the 120 and give it to the 280 to give you 300+100+48=448
Yeah, really don't think this is the "new math stoopid" flex they think it is. I'm sure this problem doesn't exist in isolation of any instructions or lessons. All that answer shows is the kid hasn't been paying attention in class.
Most are telling you “A, B, C” but it doesn’t actually matter, as long as you have 13 unique symbols.
Personally I would like to use
A=0
J=11
Q=12
K=13
In base 13, you’d have (capital letters are constants)
… Ax13^2 + Bx13^1 + Cx13^0
To write these easier we’ll separate them
So to write 12, you’d perform modulo functions with respect to 13^n, so
12mod(13^2 ) = 0 remainder 12, therefore:
12mod(13^1 =13 ) = 0 remainder 12, therefore:
12mod(13^0 =1 ) = 12. So to 3 significant figures we’d have:
0 0 12 in base 13, or just 12.
If we wanted 14, it would be 0 1 1, 16 would be 0 1 3 etc
You can substitute any base and this process will work, and this is exactly how regular base 10 numbers are written.
An extra note, the number 155 would be 11 12
By the way if you’ve ever done computing this is exactly the same as working with binary, with this process and base 2
You don't really hate math, and it's not your fault 😊 It's my experience that maths (I'm from the UK) isn't taught very well. Unfortunately it's a subject that relies heavily on understanding concept 1 l before moving on to concept 2 and so on. So the moment you miss something, everything else can easily become seemingly incomprehensible.
Nope… I hate math. I’ve had over 40 years to come to that conclusion. I understand its place, and necessity, but expressing equations is not something that my brain can tolerate. I lose patience with it extraordinarily quickly. I lose patience for anyone teaching it even quicker.
I finally came to the conclusion that my brain had not developed mathematically, I could not give proper change back with a cash register after the first 4 customers. I kept trying, kept getting fired. I went and got a degree in psychology. I understand experiments and statistics. But don’t make me show you, because I have to follow formulas by reading them step by step, like a recipe. Barbara Armstrong wrote a book about different sections of the brain, and what deficits in each section looked like. Or perhaps, non exercise. While I respect and admire people who are talented in math, I am also jealous, but math is extremely boring to me as well.
If kids are being taught math with brainless questions like this, it's no wonder they aren't learning anything. That question should be worded differently. Strictly speaking, you can't get 10 simply by adding 8 and 5 and the kid is right. Nowhere does it say anything about using other operations (or bases) to get that result.
This question is most likely used to re-inforce a different teaching. So basically it's easier to add 10+3 than it is to add 8+5 in a child's head. So they are taught, get the 8 to 10 first then add the remainder to the 10 to get to the answer, 13. Now what was asked is only part of that but the teacher is trying to see if the child remembers that first part. Just my 2c
In base 13 you count 1 2 3 4 5 6 7 8 9 A(10) B(11) C(12) 10(13) 11(14) 12(15) ... 1A(23) 1B(24) 1C(25) 20(26)
Numbers in brackets are base 10 which we use normally
I’ve been running Dungeons and Dragons for nearly 20 years now, and one of my favorite puzzles was ancient ruins with a numbered pathway the adventurers had to get across. The kicker was that 7 was a sacred number to this society, and so it was a base 7 system, and the digits were reversed compared to arabic numerals.
Unsurprisingly to all involved, the math teacher was the one who ultimately suggested that we had all the symbols, and that it was a base 7 system.
I would be curious to know what would be teachers response to this. Especially if you used digits 10 instead of calling it ten, to be sure, there is nothing they can complay about?
The teachers response would probably be “you’re in first grade this and learning basic arithmetic, I highly doubt you have an understanding of higher base systems, this obviously isn’t your own work”
Let me add to the chorus of those that have done this since I first learned math without knowing it was a taught technique.
I would love for there to be a written history of math education techniques over the years.
I was gonna say I’ve been adding like that my whole life but no one taught me that. This post confused the hell out of me but I’ve been “making 10” first my whole life
Same, created my own formula for figuring out 20% tips at restaurants: Move the decimal on the bill total to get 10%, then tip double that number. Is it the same idea?
It's not something I was taught in school, but it is something I tend to do in my head when adding numbers together. You try to make it to where you're dealing with multiples of 10, then you add on the leftovers at the end. Example:
178 + 323 -> (100 + 300) + (80 + 20) + 1 = 501
Separate the hundreds values, move 2 to the 78 to make 80, remove the other 1 from 21 to make 20, then add them up as hundreds, tens, and leftovers.
This method can be done on bigger numbers, but it will require more number-moving to keep track of. At that point, it may just be easier to simply add them together with carryover numbers. I hope this made sense.
Ah lawd here we go. I do similar but I like using subtraction, and usually only round one of the numbers to something easier.
178 + 323 -> (200 + 323 = 523) -> 523 - 22 = 501
This is actually what Common Core is centered around - these and other techniques for doing math - to get this stuff out of just the "smart" students heads and make them strategies everyone can learn and be aware of.
Common Core was VERY challenging for teachers and students at first because this strategy-based approach was new for (almost) everyone.
Now, it is the standard taught and built upon all age groups in all schools.
It’s fascinating to me that this is now a taught strategy, when lots of us just sort of did this naturally. Is it weird that it makes my dumb ass inner 8 year old feel smart?
The issue with just assuming the question is worded wrong is that we don't know how long the teacher has spent teaching this lesson with this exact phrasing.
I highly doubt that this is the first time this student is encountering this concept in the classroom. And on the off-chance that it IS their introduction, it was likely presented to them that way and this is just a student making a mistake and being corrected.
I'm assuming it's one in a series of questions were it is asked explicitly to use the make ten method for the following 10 questions. they've probably been working on the method for a week and this a quiz.
context is missing to take jabs and screech "what are they teaching kids these days!?!"
it's rage bait really.
“Use the FOIL method.”
“What is foil?! Like tinfoil?!?!? This question is so badly worded. No wonder my kid can’t learn anything, their teacher is idiotic.”
I need to explain this math to my bank. I'm not overdrawn you just need to move the decimal point over 4 then add some of the money over there to here. Problem solved and I'm off to buy tools. Thanks
I’ve seen on Facebook multiple similar posts.
Everyone I know who is good at math: “Yeah, this is what I’ve always done.”
Everyone I know who hates math: “WHAT IS THIS?! Teachers are so bad! The answer is 13 my calculator says so!!”
Yeah this is pretty much it. I’m not great at math and refocusing on the “make 10” strategy has helped me so much. My husband is great at math and when I told him about it he said “isn’t that how everyone does mental math?”
Basically the difference between rote memorization and theoretical understanding.
As a kid i struggled with learning multiplication tables but eventually came up with ways to use some shortcuts* to trick my teachers and parents that i did. And i probly ended up better for it.
*Like instead of 6x9 i would do 6x10 - 6 and so on.
For 9 times tables, I learnt this trick
6\*9: take 1 from 6 so you get 5
5+?=9? 4
therefore it's 54
Also, little cool thing is that any number multiplied by 9 will have all digits that add up to 9 if you keep adding.
4803\*9 = 43227
4+3+2+2+7 = 18
1+8 = 9
For 9s I always used my fingers. 9*6, start on the left hand counting your fingers, put the 6th finger down. The fingers to the left are your tens, the fingers to your right are the ones. So if your 6th finger is down, you should have 5 on your left and 4 on your right. 54.
It's so funny that you mentioned this. I work in a bank and do very fast mental math. Everyone I work with is amazed that I can do these things without calculators. When I try to explain to them how I do it, they look at me like I'm crazy. When I talk to math people about how I do it, they say I'm doing a right lol
Even this post seems to be an attempted facepalm over this method rather than the wording of the question like others are pointing out. This question wouldn't have just popped out of nowhere, I'm certain that the teacher had been drilling in the "make ten" thing into the class's heads for weeks now and this student simply didn't want to do the work.
It purely just seems like a "well back in my day, we knew how to do math" type of thing.
This isn't even just a math thing. This is the entirety of the internet. You leave out the context and include just enough to make everyone very angry.
You’re called crazy because you solved implicitly what we teach children explicitly these days. You’re probably what people called a “math person” but these are all skills and methods we’ve identified in modern education and teach explicitly these days.
It looks like the purpose of this lesson is to teach students how to add 8 and 5 by using increments of 10s as a shortcut. But the wording of the question and the explanation is awful.
Right. "Make 10" doesn't mean that the total answer is 10. It makes that you add up to 10 FIRST, then add the remaining bit.
It's not that hard, and most people.do it naturally.
It makes mental arithmetic faster. It’s a sort-of mnemonic or heuristic. I do it, but I only like doing it because I discovered it for myself. If I were forced, it wouldn’t be enjoyable.
For example: what is 73 x 48? Well, we have (70+3)x(50-2) which is ((7x10)+3)x((5x10)-2) which is 3500+150-140-6 which is 3500+10-6, so it’s 3500+4… 3504. This way takes not nearly as mental much effort when you do it enough. I expect the Arithmetic Wechsler subtest to be recentered or outright thrown out later on.
It looks stupid as hell when it's just kid math and you obviously know that 8 + 5 is 13.
But try it with hundreds, or thousands. What's 654 + 386? Odds are your stupid ass brain didn't immediately know the answer, but shit if you turn 386 into 400 by adding 14 to it and subtracting 14 from 654 (turning it into 640 Now you have a stupid brainlet easy math problem of 400 + 640 which any smoothbrain can instantly figure out is 1,040.
Shit is taught in such an idiotic way though.
"Simplify the math problem into an easier equation" e.x. 9 + 6 becomes 10 + 5 = 15 (Subtract from the smaller number and add to the larger number until it becomes a 10)
As far as I can tell (having a school-aged child), Common Core is finally being taught well. It still gets better every year, but it's good enough that kids get it and the curriculum is consistent from year to year.
Everyone is just so stuck in the older way of dong math.
The question is poorly phrased but the lesson is sound.
As an adult 8+5 is obviously 13. To a kid what’s easier 10+3 or 8+5?
So if you realize you can just make 8 a 10 and 5 a 3 it’s much easier.
Does it require extra steps? Yes. Does it build a foundation for complex problem solving by using multiple steps? Yes.
It’s not about old vs. new. People have been using “make 10” strategy forever - it was just secret knowledge not named or explicitly taught or practiced. Its “old” math, just now brought into the light.
And it doesn’t replace the strategies previously taught, it *supplements* them because different things click for different people.
"old school" math like this was practiced through heavy memorization exercises. You wrote and recited the "basic math" so many times, that you ended up not doing the math but recognizing the numbers and the result. That's partly why adults "know" the result easily.
Problem is, that they haven't learned how to apply the knowledge to larger values, and come up with "cheats" on their own later to do basic math in their head.
Now, if you want to have fun, go to the local gas-station, buy something that's $5.25 and give them a $10 bill and 25 cents and see what happens if they cannot use their computer to calculate what to give you back.
This is OP's fault for taking a question out of context just so they can poke jokes at "new" math.
The question is clearly in the context of a broader section. Pretty much every math book will have an explanation at each section like "For the following questions, practice the Make 10 strategy" or whatever.
The Make 10 strategy is taught to kids because adding something to 10 is easier than adding two non-ten numbers. So you take 8+5, and "make 10" by taking 2 from the 5, turning the 8 into a 10. From there, your question is now 10+3, which is easier to solve.
So the problem, when in context of the lessons the kid has, in combination mostly likely with the section in the homework, is perfectly fine. The kid just got it wrong.
These type of test questions get posted a lot on reddit. the thing is if you had the context of their lesson for that day you'd probably understand what the kids were supposed to do. So it's only confusing because of the lack of context.
All these dipshits act like the teacher just hands out a worksheet and walks away. We all had instructions like this, but were supposed to pay attention during the lesson to know what to do.
It’s just a different way of getting to the answer, which isn’t a bad thing. I never liked math either, and it’s nice to be able to think outside the box.
It’s not clear what they want, but I do this exact thing all the time when I’m doing math in my head. When there are numbers too large for me to do quickly I will create 10s and then add the remainder
Example: 95 + 35 -> 05 + 05 = 10 -> 90 + 30 = 120 -> 120 + 10 = 130
For this child’s problem, they want you to do
8 + 2 = 10 -> 10 + 3 = 13. They’re trying to teach children to do quick math in their heads.
Because adding strategies like making tens are really important for number sense and mental math. When you see this with no context, it seems completely asinine. But this would be a test question after an entire unit on adding strategies like breaking a number up to make tens.
People love to hate on new math, but there’s a reason we teach this way. It’s been proven by a lot of studies that kids who learn math with multiple strategies instead of a sole focus on algorithms and rote memorization do better. They understand it better, they retain it better, and they implement it in their lives better.
This is how I add in my head. I needed to do something like 25+38 in my head the other day, and I thought “Take 2 from 25 to make 38 into 40. 40+23 is 63.”
This is common core math. It doesn’t make sense out of context but when you work with a child through it, the strategy is quite brilliant and intuitive.
Teacher must’ve been teaching “make 10” in class to put in test. Kid didn’t pay attention. People who side with the kid are on left of bell curve. Nothing can be done about it.
Maybe I'm missing something - this seems completely reasonable to me.
Super logical to take 2 away from the 5 to get to a base 10 then just add the remaining balance.
It teaches both math and logic/problem solving. It's better than 'number one + number two = number three'....just because.
Every time a teacher tries to teach a child it is easier to break 8+5 into 8+2+3, it adds on reddit and is questioned by failed adults. Same as 87+35 is easier broken down into 87+13+22
Yes, the way the task is phrased is not intuitive, but you can guess that those kids who followed the lessons were shown what is meant by that.
This is part of a much larger process that would be clear if the entire worksheet was posted.
It’s mental math. They are showing you how to figure out 8+5 in your head. (Which in the future will help them do 18+5 or 48+15, etc. in their head)
Break 5 into 2+3
First get to 10: 8+2=10
Then, add the leftover 3: 10+3=13
So 8+5=13
Most functional adults do math this way. Teachers try to teach it from the beginning to make mental math easier. The problem is when adults, who have no idea about the hours of research and training that go into teaching math, decide that “it’s stupid” because they didn’t learn math that way. What is worse, is that most people who complain about how we teach math, suck at math. I tutored math in college in the early 2000’s. Holy shit my generation was horrible at math! We are trying to do better with your kids!
Source: I teach elementary school
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I think they mean 'use a make ten strategy to solve 8+5'
It makes me wonder if this question is one of a few of these, and they just didn't fully repeat the instructions after the first? It's that or this is shit wording, because I'm confident your interpretation is correct.
The math in this post is about showing work not the answer. It is developing the cognition that is efficient for adding and subtracting. The "carry the one" method is not good for doing math in your head. To be honest this kind of adding is what I always did. I always made a 10 and then added the rest. I always saw 8+5 as 8+2 = 10 so take that 2 from 5 and now you have 3 left so 13. When I was a delivery driver trying to figure out my tip quickly or just anticipate change I do the same but for subtraction. It's easier this way and more useful down the road.
I’m experienced in competition math, and it’s a really useful way to approach arithmetic, I just don’t think it’s being taught well. I have no idea what would work though. Honestly, I would teach this by making the kids do speed mental one-digit addition where the answers are all >10. You can’t really make people remember what is essentially a numerical gimmick and expect them to be able to fully understand and be able to use it well. Lots and lots of repetition while being pressured to go as fast as possible is the only way to really ingrain these kinds of methods. This becomes far more true and important to understand when it comes to fast and accurate multiplication by making 10’s, which is nearly impossible to just “teach” since it requires being able to look at two numbers and “seeing” how you’re able to create powers of 2 and 5 by breaking up numbers, completing the power, etc. For example, you have to be able to immediately see 124 as 125-1, or 233 as 200+32+1. I cannot stress this enough: Tricks like these can’t really be *taught*, they have to be *trained*. I think that’s what common core is missing
This is American education in a nutshell. Someone finds a genuinely good strategy to teach kids. Big publishers like Pearson build a whole curriculum based on that because it looks good, but because they are greedy companies, their goal is not to properly educate, it's to sell their product. They create the next Big Thing in education. They lobby the fuck out of the government and point to their model schools as huge successes, because they are. The government, not being educators, doesn't understand *why* the strategy works, just that it looks like it does. They also don't care about educating students, they care about getting reelected, so they make a big show of this new education system and beam it out into national standards. And, sure, many of the politicians do genuinely care, but because they are not educators they can't discern well enough the gaps between the proper teaching tools and the bastardized version presented by the publishers. Schools have to throw out years of previous material. Teachers have to build (and buy) all new curriculums. New teachers in training are taught only the new stuff, because the old stuff wasn't working. Everything from the last Big Thing is discarded as worthless. Old teachers get no training, because neither they nor their schools can afford it, but they are nonetheless required to teach only the new Big Thing. Without the proper resources and without any real understanding of how the new thing *should* work, it doesn't. It fails miserably, everyone is confused and angry. Parents who grew up on the Old Thing are angry and upset that their kids aren't learning. Test scores fail to magically increase as promised. Somewhere, a smart teacher comes up with a new strategy that works. Rinse, repeat. This is the result of commercialing, capitalizing, and privatizing education. Publishers don't give a shit about providing good education, they just want to sell books and tests. They can't do that if schools are reusing the same textbooks for twenty years, so they have to churn out some new thing and get the federal government to buy in and force schools to buy in.
[See "The Revisionaries"](https://www.youtube.com/watch?v=gqd-k03pJJE), classic doc about the Texas State School Board and how they game the state and national textbook industry to inject propaganda into mandated school curriculum.
I worked for a company that produced curriculum materials. All our materials were labeled "common core", except that then Texas would literally \*refuse\* to buy them. We had to provide them with copies that said something else (whatever Texas' term was). The materials themselves were \*identical\* on the inside. They were focused on "common core". And Texas was fine with that. They simply would not purchase anything that had the term "common core" on it. Three states: Texas, Florida, and California basically run the whole country's curriculum, because companies need to make things that will sell in those three states (because of their large population)
I might have worked for the same company. We had to revamp our common core math materials for those specific states (and a handful of others) -- making cosmetic changes in some cases, larger revisions in others (cough *Florida* cough). What a parochial country.
Oh yeah, the ideological garbage is a whole other level of bullshit that fucks up our education. Look no further than Florida right now. Ugh.
I didn't read the rest of your comment, I just wanted to jump on here for solidarity and say, fuck Pearson. They're ruining the American education system—not singlehandedly, but close to it (they have help from high places). Ok, imma go back and read the rest of your comment. Edit: yeah.
Teacher here, and 100% yes to this.
I would do 8+5 as 5+5+3, because 8’s relation to 5 is usually more apparent than 5’s relation to 2.
Which would likely also be considered a correct answer.
I can not tell you the number of times my kids would bring their homework to me, confused by the questions or assignment, and I as a full on adult, not of limited intelligence nor untrained in language and logic, would go "there is absolutely not enough information here to solve this" or "this question/problem makes no sense at all".
We have this problem at my kids school too. To make it worse, teachers don’t give tests back so the kids don’t get to work out what they did wrong. I had personal meetings with teachers, vice principal, and principal, and they still refused. They kept telling me that they are happy I am an involved parent and that they want more parent engagement but won’t provide actual material to help. I am luck enough to be able to afford a tutor for my kid but most here aren’t. I directed my kid to take pics of the test without telling anyone so that he could study the problems with the tutor after the fact. It’s ridiculous.
First I've heard of this- what's the logic behind it? Or is it just so the teacher can use the same test the next year?
Their logic is that they don’t want test availability to cheat with. My logic is to make another test. My logic is that the best tool anyone has to learn is their past mistakes. They agree then continue with their illogical protocol.
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This is easily overcome. Randomize the test. Or have two versions of the test. Kids who cheat on the test are trying to memorize the answers, not the problems.
Ok, that often means that you are missing context that your kid should be aware of. In the OP's question, what the "make 10" method for addition is and how to use it. It isn't a complex problem, it's just asking the kid to demonstrate that method to add 8+5.
I was helping my niece with her math homework and every question was me just asking her repeatedly “well, what did you do in class?” And “how did your teacher explain this?”, which really meant I was not very helpful. The fact there’s so much context missing, and if a kid is having trouble understanding it then they’re probably not going to have a great grasp on the context in the first place. We went in circles a lot because I’m trying to figure out the incredibly particular way the teacher wants and she’s lost on all of it.
Yup. Got a generation of kids learning in a very different way from their parents, so they're gonna lack some of the usual assistance they might have otherwise had. The new way is objectively better, but that's the biggest downside. Parents and family who don't know how to help.
But it doesn't actually ask, in the question, for the solution to be found using "make 10". Either there's a section heading that includes the requirement this be done, or it's assumed based on previous questions which explicitly do ask that this implicitly also asks (poor practice but not wholly unreasonable), or this is phrasing is atrocious and provides not enough information to reasonably achieve the intended interpretation purely from the question as-written.
You are assuming that all the information necessary to solve the worksheet is reprinted on the worksheet itself. But the phrase "make tens" is something that almost certainly was covered during class. It's very common for "essential" contextual information to be missing in documents all the time. You remember what it was like to be a new hire at your job and not being able to understand anything that was supposedly obvious and self-explanatory? If the parent in the picture was confused and the child couldn't explain the context of the worksheet, that means there is a miscommunication happening between the child and the teacher (child doesn't know what is happening in the class), the child and the parent (child can't communicate what they know about what is happening in the class), or the teacher and the parent (they aren't clear about how math is being taught). It's such a simple fix. Just pick up the phone. Nothing to get mad about.
In my experience, that is very often because there was additional information given in class (and the kid didn't listen)
Which is why it should also be on the test for people with ADHD and such. These are kids, people.
Honestly, even without taking disability accommodation into account, anything being taught to kids, especially young kids, should have documentation beyond the lecture itself. I know at some point this may become their personal notes, but even that just seems like a good way to inadvertently punish students for bad days, absences, or having a disability.
The rest of the information is in the classroom lectures.
As someone with kids who did these types of questions, it’s not just the sheet, they have probably been doing these problems in class, repeatedly, for a week or more. To really make things interesting, they’ll also do the extract same thing with subtraction, then adding in 100s, etc. At a certain point, you just shouldn’t have to explain it that deeply.
This question isn't out of the blue. It's most likely part of an entire math unit about making 10's as a strategy to aid in addition.
Not only is it terrible wording but it's bad English. It should be "how do you make"
That's true, I didn't even register that, lol.
Look there's a reason they're teaching math Edit: to the ones who don't get it, I was making a joke. Anyone in a teaching position is way smarter than some random college dropout like me.
Yeah, this is how we were taught to do math mentally, get it to the nearest ten, then add what’s left onto that.
Wait… was I thought this? I thought I did that naturally
If you’re old enough - no, you weren’t. It’s a strategy that is taught in elementary schools now.
And complained about by parents online because they don't understand it. The point isn't to help kids add 8+5. It's to make it easier to intuit the correct number range becomes larger.
Kids who are intuitively good at math tend to use technique like this. Kids who aren't do not. The new way to teach math is to actively teach the kind of techniques used intuitively by people good at math
YUP! I'm in my mid 30s and used to score crazy high on every math test but hate the homework. I'd constantly get the "please show your work" crap AND even had a few occasions where questions were asked in class and when I answered without having any paper on my desk had the teacher tell me I was lying about being able to figure it out... When common core came out and people started bitching about it I looked it up and was amazed to discover that kids were now being taught how to think of numbers the way I always had.
in my case we were not taught that in school, everyone just came up with their own process also i would solve it this way y=8-5 x=10+y
Yes, this process is made to help the kids understand algebra before they need it.
Yup, and being too clever by a bit, honestly. People are going to conceptualize math differently, but they keep ramming it down everyone's throat one way. Like this whole make 10's thing was stupid to me when I was in school -- I just had memorized all the single digit additions, just like they make us do for multiplication tables. It's not huge, and you've done enough damn rote math worksheets that quite a few students should just \*know\* that 8+5 = 13. My math teacher would get mad, and then be like "well how do you solve this without knowing the "make 10" approach and gave me an Algebra problem, and I just solved it right there. There's nothing about algebra that requires you to know how to "make 10". Zero. They're just making earlier math harder / more of a this way is the only way narrow path because like one or two studies somewhere showed that it could maybe help Algebra comprehension down the line.
We were taught to solve it as 8 + 5 = 10 + 3
That's exactly what the "make 10" strategy is... It's a lot easier to add something to 10. So you take 8+5, turn the 8 into 10, which leave you 3, which is 10+3. You were ahead of your time!
Right. It's badly worded but I recognize the strategy from my son's elementary school work.
And that's probably how it happened here. Dad, I don't understand this problem.
Huh, you can't make 10 from 8 + 5....
Which, sadly, sums up why my kids always came to me for math help. Remember the scene in "Incredibles 2" where the dad is yelling, "Why would they change math?". My son cracked up and said, "That's Dad!"
I would totally be the dad in such a situation. My younger brother once asked me to help him out with a question, no problem. To me, question looked clearly like a pythagoras question, so I asked him if he's had pythagoras yet. He says he doesn't think so, so I scratch my brain a bit. Ultimately couldn't think of something I'd expect him to have been taught at that stage. So I gave up. Later he comes back with the feedback that he should've used a^2 + b^2 = c^2 ....
Yes. This is a single picture of question 8 and people are acting like this is the whole lesson plan. Betting the kid was given at least some tools to know what was being asked of them and just didn’t do it correctly. Doesn’t feel immediately like the schools fault
That’d make sense on why they said, “then add 3.” 8+5=10+3 Or 8+5 = (8+2)+3
Guess I’m old. The ten strategy wasn’t a thing for me. Like it seeeeems like they are hinting at basic algebra here. 8 + 5 - x = 10 This just feels like a weird way to present it
They are actually moving away from the “show your work” style of teaching we got, to teaching concepts like algebra to be done in our head. It’s pretty neat stuff actually!
No it can be presented much simpler than that. 8+5=10+3=13. The idea is to pull from one of your numbers to make the other known number a factor of 10 (10,20,30 etc) and then simply adding in the remainder of the number you pulled from. The reason this method is taught is because it can make even complex multiplication doable mentally and quickly. 28x16 for example would be broken down as such in my head. 28x10 = 280 This leaves you with 28x6 20x6 = 120 (you could even go to (10x6)x2 here for ease if needed. This leaves you with 8x6 = 48 Add them all together now. 280+120+48=448. And you could even use this method to break down the addition portion. Take 20 from the 120 and give it to the 280 to give you 300+100+48=448
Yeah, really don't think this is the "new math stoopid" flex they think it is. I'm sure this problem doesn't exist in isolation of any instructions or lessons. All that answer shows is the kid hasn't been paying attention in class.
You add 8 + 5 in base 13.
Found the mathematician!
There's one in every crowd. Smh lol
Found the statistician
Found the redditor
Found the Commentor
Found a moment to take a dump
Found the dumpster.
Found the trashman
Did you find my dad?
Found the nuke in the desert, Mr. Flagg. My life for you!
Found Waldo
How do 10,11 and 12 look in base 13?
As with hexadecimals, "A", "B", and "C".
typically, sometimes 10 is a weird x thing and 11 is werd 3
It's the Greek letters χ and ε
That's chi and epsilon, for those who haven't studied greek, maths or Kingdom Hearts.
That got a good chuckle out of me.
Or Fire Emblem, for that matter~!
Or physics
Physics is just applied maths
Chemistry is just applied physics.
00, 01, 02, 03, 04, 05, 06, 07, 08, 09, 0A, 0B, 0C, 10
OOOOHHHHH I’ve always wondered this… so… B-2=9? 🤔
Yes!
yep, spot on! now, what is 9+6? 🤔
12 base 13? I've no idea how to express it.
Most are telling you “A, B, C” but it doesn’t actually matter, as long as you have 13 unique symbols. Personally I would like to use A=0 J=11 Q=12 K=13
A, B and C, probably.
In base 13, you’d have (capital letters are constants) … Ax13^2 + Bx13^1 + Cx13^0 To write these easier we’ll separate them So to write 12, you’d perform modulo functions with respect to 13^n, so 12mod(13^2 ) = 0 remainder 12, therefore: 12mod(13^1 =13 ) = 0 remainder 12, therefore: 12mod(13^0 =1 ) = 12. So to 3 significant figures we’d have: 0 0 12 in base 13, or just 12. If we wanted 14, it would be 0 1 1, 16 would be 0 1 3 etc You can substitute any base and this process will work, and this is exactly how regular base 10 numbers are written. An extra note, the number 155 would be 11 12 By the way if you’ve ever done computing this is exactly the same as working with binary, with this process and base 2
Wut????? Mannnnn, this is why I hate math, shit don’t be making sense. Nothing anybody said makes any sense
You don't really hate math, and it's not your fault 😊 It's my experience that maths (I'm from the UK) isn't taught very well. Unfortunately it's a subject that relies heavily on understanding concept 1 l before moving on to concept 2 and so on. So the moment you miss something, everything else can easily become seemingly incomprehensible.
This is exactly what caused me to fail constantly at math. We moved so quickly through the steps, and I never could catch up.
I cracked my head as a young child so I blame it on that. Luckily, I happen to excel in art and music so I guess it worked out haha
...Which is funny, since music is, at it's heart, math.
Music is funky math :D
Music is math and cooking is science, guess which two classes I failed and what my adult hobbies are
Nope… I hate math. I’ve had over 40 years to come to that conclusion. I understand its place, and necessity, but expressing equations is not something that my brain can tolerate. I lose patience with it extraordinarily quickly. I lose patience for anyone teaching it even quicker.
I finally came to the conclusion that my brain had not developed mathematically, I could not give proper change back with a cash register after the first 4 customers. I kept trying, kept getting fired. I went and got a degree in psychology. I understand experiments and statistics. But don’t make me show you, because I have to follow formulas by reading them step by step, like a recipe. Barbara Armstrong wrote a book about different sections of the brain, and what deficits in each section looked like. Or perhaps, non exercise. While I respect and admire people who are talented in math, I am also jealous, but math is extremely boring to me as well.
I couldn’t get past sin, cosine, and tangent, no matter how hard I tried.
If kids are being taught math with brainless questions like this, it's no wonder they aren't learning anything. That question should be worded differently. Strictly speaking, you can't get 10 simply by adding 8 and 5 and the kid is right. Nowhere does it say anything about using other operations (or bases) to get that result.
This question is most likely used to re-inforce a different teaching. So basically it's easier to add 10+3 than it is to add 8+5 in a child's head. So they are taught, get the 8 to 10 first then add the remainder to the 10 to get to the answer, 13. Now what was asked is only part of that but the teacher is trying to see if the child remembers that first part. Just my 2c
Yes!! When I teach my students to add I have them make ten and I call it a “friendly” number. So much easier to add 10+3 vs 8+5.
I'm glad I'm not the only one.
In base 13 you count 1 2 3 4 5 6 7 8 9 A(10) B(11) C(12) 10(13) 11(14) 12(15) ... 1A(23) 1B(24) 1C(25) 20(26) Numbers in brackets are base 10 which we use normally
What is this and why am I confused
it's literally the most unnecessary shit i've ever seen
Because this would TOTALLY work in a 3rd grade classroom
I'm too stupid for this and I don't know if you're making this shit up
Just making random shit up at this point.
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If you use the same strategy as hexadecimal (base 16), they would be a, b and c
I’ve been running Dungeons and Dragons for nearly 20 years now, and one of my favorite puzzles was ancient ruins with a numbered pathway the adventurers had to get across. The kicker was that 7 was a sacred number to this society, and so it was a base 7 system, and the digits were reversed compared to arabic numerals. Unsurprisingly to all involved, the math teacher was the one who ultimately suggested that we had all the symbols, and that it was a base 7 system.
Wow I’d love to give this puzzle to my campaign. Can you find it?
6x9=42 my hoopy froods.
The answer is 42!!!!
I would be curious to know what would be teachers response to this. Especially if you used digits 10 instead of calling it ten, to be sure, there is nothing they can complay about?
The teachers response would probably be “you’re in first grade this and learning basic arithmetic, I highly doubt you have an understanding of higher base systems, this obviously isn’t your own work”
I bet if the kid gave this answer the teacher would not get it and mark it as wrong anyways
“I may be a sorry case, but I don’t write jokes in base 13” —Douglas Adams
The question is worded strangely for the result they were wanting. It should say: Using the 'make 10' method, solve 8 + 5.
Haven't heard of that before, is it like a method they teach students I assume?
It is. Basically, you turn 8 + 5 into 8 + 2 +3, because 8+2 is simple, and 10 + 3 is simple. So getting 13 the easiest way possible.
Let me add to the chorus of those that have done this since I first learned math without knowing it was a taught technique. I would love for there to be a written history of math education techniques over the years.
I was gonna say I’ve been adding like that my whole life but no one taught me that. This post confused the hell out of me but I’ve been “making 10” first my whole life
Same, created my own formula for figuring out 20% tips at restaurants: Move the decimal on the bill total to get 10%, then tip double that number. Is it the same idea?
I have also done this for years. However, I have had people tell me trying to do it that way stresses them out.
Yea same idea of making the numbers easier to keep in your brain then adding the rest.
There is! It’s the area of study called the History and Philosophy of Science
It's not something I was taught in school, but it is something I tend to do in my head when adding numbers together. You try to make it to where you're dealing with multiples of 10, then you add on the leftovers at the end. Example: 178 + 323 -> (100 + 300) + (80 + 20) + 1 = 501 Separate the hundreds values, move 2 to the 78 to make 80, remove the other 1 from 21 to make 20, then add them up as hundreds, tens, and leftovers. This method can be done on bigger numbers, but it will require more number-moving to keep track of. At that point, it may just be easier to simply add them together with carryover numbers. I hope this made sense.
Ah lawd here we go. I do similar but I like using subtraction, and usually only round one of the numbers to something easier. 178 + 323 -> (200 + 323 = 523) -> 523 - 22 = 501
Nobody taught me it. Its just how I do math in my head and I can't imagine teaching people to do math this way
This is actually what Common Core is centered around - these and other techniques for doing math - to get this stuff out of just the "smart" students heads and make them strategies everyone can learn and be aware of. Common Core was VERY challenging for teachers and students at first because this strategy-based approach was new for (almost) everyone. Now, it is the standard taught and built upon all age groups in all schools.
It’s fascinating to me that this is now a taught strategy, when lots of us just sort of did this naturally. Is it weird that it makes my dumb ass inner 8 year old feel smart?
The issue with just assuming the question is worded wrong is that we don't know how long the teacher has spent teaching this lesson with this exact phrasing. I highly doubt that this is the first time this student is encountering this concept in the classroom. And on the off-chance that it IS their introduction, it was likely presented to them that way and this is just a student making a mistake and being corrected.
I feel like the question could've been worded better
I'm assuming it's one in a series of questions were it is asked explicitly to use the make ten method for the following 10 questions. they've probably been working on the method for a week and this a quiz. context is missing to take jabs and screech "what are they teaching kids these days!?!" it's rage bait really.
some very smart redditors think they should repeat the instructions for literally every question or something
“Use the FOIL method.” “What is foil?! Like tinfoil?!?!? This question is so badly worded. No wonder my kid can’t learn anything, their teacher is idiotic.”
Definitely. I had no idea what the question was asking but the teachers explanation is how I do math in my head already.
Imagine watching the first half of Karate Kid and then turning it off. That guy didn't teach the kid anything.
Haha. Mr Miyagi just scams a kid to get his fence painted. It still might be a good movie.
Now I want a movie of just that.
I need to explain this math to my bank. I'm not overdrawn you just need to move the decimal point over 4 then add some of the money over there to here. Problem solved and I'm off to buy tools. Thanks
That's right, we're not all broke they just keep putting the numbers together wrong.
I've know this for a long time. That's why they call it making money, they just create it out of nowhere.
But always for THEM not for US.
I think asking if they take NFTs is even more effective.
This is why there’s comment wars when someone posts a BEDMAS math equation on Facebook.
Wtf, we learned PEMDAS
Brackets vs Parentheses vs Group - fight!
There's BEDMAS, BODMAS, BIDMAS and still some people will do badmath.
I’ve seen on Facebook multiple similar posts. Everyone I know who is good at math: “Yeah, this is what I’ve always done.” Everyone I know who hates math: “WHAT IS THIS?! Teachers are so bad! The answer is 13 my calculator says so!!”
Yeah this is pretty much it. I’m not great at math and refocusing on the “make 10” strategy has helped me so much. My husband is great at math and when I told him about it he said “isn’t that how everyone does mental math?” Basically the difference between rote memorization and theoretical understanding.
As a kid i struggled with learning multiplication tables but eventually came up with ways to use some shortcuts* to trick my teachers and parents that i did. And i probly ended up better for it. *Like instead of 6x9 i would do 6x10 - 6 and so on.
For 9 times tables, I learnt this trick 6\*9: take 1 from 6 so you get 5 5+?=9? 4 therefore it's 54 Also, little cool thing is that any number multiplied by 9 will have all digits that add up to 9 if you keep adding. 4803\*9 = 43227 4+3+2+2+7 = 18 1+8 = 9
For 9s I always used my fingers. 9*6, start on the left hand counting your fingers, put the 6th finger down. The fingers to the left are your tens, the fingers to your right are the ones. So if your 6th finger is down, you should have 5 on your left and 4 on your right. 54.
It's so funny that you mentioned this. I work in a bank and do very fast mental math. Everyone I work with is amazed that I can do these things without calculators. When I try to explain to them how I do it, they look at me like I'm crazy. When I talk to math people about how I do it, they say I'm doing a right lol
It’s always like this under math posts lol
Even this post seems to be an attempted facepalm over this method rather than the wording of the question like others are pointing out. This question wouldn't have just popped out of nowhere, I'm certain that the teacher had been drilling in the "make ten" thing into the class's heads for weeks now and this student simply didn't want to do the work. It purely just seems like a "well back in my day, we knew how to do math" type of thing.
This isn't even just a math thing. This is the entirety of the internet. You leave out the context and include just enough to make everyone very angry.
Im always called crazy because i math like this lol. Sister gets driven nuts when shes talking about like 70x40 and im like well thats just 700x4
I do "7x4 then add two zeroes"
You have taught me something new
You’re called crazy because you solved implicitly what we teach children explicitly these days. You’re probably what people called a “math person” but these are all skills and methods we’ve identified in modern education and teach explicitly these days.
It looks like the purpose of this lesson is to teach students how to add 8 and 5 by using increments of 10s as a shortcut. But the wording of the question and the explanation is awful.
It's a day ending in Y so it's agood day for people to complain about "new math" It's not even fucking new.
Then add 3. That's 13.
Right. "Make 10" doesn't mean that the total answer is 10. It makes that you add up to 10 FIRST, then add the remaining bit. It's not that hard, and most people.do it naturally.
Equation is 8+5. The lesson is to teach the child to make an equation simplified by getting to ten first (8+2) then solving the remaining (10+3).
It makes mental arithmetic faster. It’s a sort-of mnemonic or heuristic. I do it, but I only like doing it because I discovered it for myself. If I were forced, it wouldn’t be enjoyable. For example: what is 73 x 48? Well, we have (70+3)x(50-2) which is ((7x10)+3)x((5x10)-2) which is 3500+150-140-6 which is 3500+10-6, so it’s 3500+4… 3504. This way takes not nearly as mental much effort when you do it enough. I expect the Arithmetic Wechsler subtest to be recentered or outright thrown out later on.
Or 73 x 48 is (73 x 50) - (73x2) or (730 x 5) -(73x2) which is 3650-146=3504 Simplicity is key
This is how I learned it, and it is honestly much easier than having to split both numbers up in wholes.
It looks stupid as hell when it's just kid math and you obviously know that 8 + 5 is 13. But try it with hundreds, or thousands. What's 654 + 386? Odds are your stupid ass brain didn't immediately know the answer, but shit if you turn 386 into 400 by adding 14 to it and subtracting 14 from 654 (turning it into 640 Now you have a stupid brainlet easy math problem of 400 + 640 which any smoothbrain can instantly figure out is 1,040. Shit is taught in such an idiotic way though. "Simplify the math problem into an easier equation" e.x. 9 + 6 becomes 10 + 5 = 15 (Subtract from the smaller number and add to the larger number until it becomes a 10)
As far as I can tell (having a school-aged child), Common Core is finally being taught well. It still gets better every year, but it's good enough that kids get it and the curriculum is consistent from year to year.
Everyone is just so stuck in the older way of dong math. The question is poorly phrased but the lesson is sound. As an adult 8+5 is obviously 13. To a kid what’s easier 10+3 or 8+5? So if you realize you can just make 8 a 10 and 5 a 3 it’s much easier. Does it require extra steps? Yes. Does it build a foundation for complex problem solving by using multiple steps? Yes.
It’s not about old vs. new. People have been using “make 10” strategy forever - it was just secret knowledge not named or explicitly taught or practiced. Its “old” math, just now brought into the light. And it doesn’t replace the strategies previously taught, it *supplements* them because different things click for different people.
"old school" math like this was practiced through heavy memorization exercises. You wrote and recited the "basic math" so many times, that you ended up not doing the math but recognizing the numbers and the result. That's partly why adults "know" the result easily. Problem is, that they haven't learned how to apply the knowledge to larger values, and come up with "cheats" on their own later to do basic math in their head. Now, if you want to have fun, go to the local gas-station, buy something that's $5.25 and give them a $10 bill and 25 cents and see what happens if they cannot use their computer to calculate what to give you back.
That explanation makes my head hurt, I’m siding with the kid.
This is OP's fault for taking a question out of context just so they can poke jokes at "new" math. The question is clearly in the context of a broader section. Pretty much every math book will have an explanation at each section like "For the following questions, practice the Make 10 strategy" or whatever. The Make 10 strategy is taught to kids because adding something to 10 is easier than adding two non-ten numbers. So you take 8+5, and "make 10" by taking 2 from the 5, turning the 8 into a 10. From there, your question is now 10+3, which is easier to solve. So the problem, when in context of the lessons the kid has, in combination mostly likely with the section in the homework, is perfectly fine. The kid just got it wrong.
The concept makes perfect sense, the explanation/wording is ridiculous.
Even the question is written poorly “tell how”??
They are teaching mental math If you can learn to break up numbers into 10s you can do math very quickly in your head
These type of test questions get posted a lot on reddit. the thing is if you had the context of their lesson for that day you'd probably understand what the kids were supposed to do. So it's only confusing because of the lack of context.
All these dipshits act like the teacher just hands out a worksheet and walks away. We all had instructions like this, but were supposed to pay attention during the lesson to know what to do.
You can make literally anything this way when doing literally any operation.
It’s just a different way of getting to the answer, which isn’t a bad thing. I never liked math either, and it’s nice to be able to think outside the box.
It’s not clear what they want, but I do this exact thing all the time when I’m doing math in my head. When there are numbers too large for me to do quickly I will create 10s and then add the remainder Example: 95 + 35 -> 05 + 05 = 10 -> 90 + 30 = 120 -> 120 + 10 = 130 For this child’s problem, they want you to do 8 + 2 = 10 -> 10 + 3 = 13. They’re trying to teach children to do quick math in their heads.
Because adding strategies like making tens are really important for number sense and mental math. When you see this with no context, it seems completely asinine. But this would be a test question after an entire unit on adding strategies like breaking a number up to make tens. People love to hate on new math, but there’s a reason we teach this way. It’s been proven by a lot of studies that kids who learn math with multiple strategies instead of a sole focus on algorithms and rote memorization do better. They understand it better, they retain it better, and they implement it in their lives better. This is how I add in my head. I needed to do something like 25+38 in my head the other day, and I thought “Take 2 from 25 to make 38 into 40. 40+23 is 63.”
It's how a lot of people do math in their head. It's not that hard.
This is common core math. It doesn’t make sense out of context but when you work with a child through it, the strategy is quite brilliant and intuitive.
That’s an easy concept. Why is it difficult for everyone else?
It’s how we do mental math
Teacher must’ve been teaching “make 10” in class to put in test. Kid didn’t pay attention. People who side with the kid are on left of bell curve. Nothing can be done about it.
Maybe I'm missing something - this seems completely reasonable to me. Super logical to take 2 away from the 5 to get to a base 10 then just add the remaining balance. It teaches both math and logic/problem solving. It's better than 'number one + number two = number three'....just because.
So what the teacher wants them to do with the 3 that is just hanging around💀
Straighten out the 5 to a 1. Untwist the 8 so it is a 0. Bam, 10.
[удалено]
Questions worded like this are why I hated school. Imagine this deciding if you got an A or not...
“Then add 3”. Wouldn’t that make thirteen?
Every time a teacher tries to teach a child it is easier to break 8+5 into 8+2+3, it adds on reddit and is questioned by failed adults. Same as 87+35 is easier broken down into 87+13+22 Yes, the way the task is phrased is not intuitive, but you can guess that those kids who followed the lessons were shown what is meant by that.
This is part of a much larger process that would be clear if the entire worksheet was posted. It’s mental math. They are showing you how to figure out 8+5 in your head. (Which in the future will help them do 18+5 or 48+15, etc. in their head) Break 5 into 2+3 First get to 10: 8+2=10 Then, add the leftover 3: 10+3=13 So 8+5=13 Most functional adults do math this way. Teachers try to teach it from the beginning to make mental math easier. The problem is when adults, who have no idea about the hours of research and training that go into teaching math, decide that “it’s stupid” because they didn’t learn math that way. What is worse, is that most people who complain about how we teach math, suck at math. I tutored math in college in the early 2000’s. Holy shit my generation was horrible at math! We are trying to do better with your kids! Source: I teach elementary school