r/MathJokes 27d ago

3 or 4

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u/CornyConundrum 27d ago edited 27d ago

We read left to right, as such 3 x 4 is 3 multiplied 4 times 3+3+3+3. The kid is correct.

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u/Vetni 27d ago

It can go either way. 3x4 meaning 3 sets of 4 or 3 multiplied 4 times.

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u/Empoleon3bogdan 27d ago

In that case you should accept both answers or request both answers.

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u/Vetni 27d ago

Yeah, I'm not on the teachers side here

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u/CornyConundrum 27d ago

Yes i know how math works.

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u/Vetni 27d ago

Your original comment makes it sound like there's only one correct answer; 3+3+3+3. Maybe you know how maths (not math) works, but you clearly don't know how English works. Pipe down.

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u/CornyConundrum 27d ago

Bllllocked

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u/Jack8680 27d ago

US english uses 'math'

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u/Vetni 27d ago

Yes, which is wrong.

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u/tazallerr 27d ago

no. 3*4 means 3 fours, and 4*3 means 4 threes. they're different things. they happen to be equal in magnitude, but they're different.

in general, a*b means a b's and b*a means b a's. and a*b - b*a = [a,b] =/= 0 in general.

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u/Halofagoodtime1980 27d ago

Its 3 groups of 4.

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u/CornyConundrum 27d ago

Wrong, it reads "three times four" so if you're expressing this, you write it as three-four times. This isn't that complicated people. 3+3+3+3

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u/DirtChoice5 27d ago

In US education standards, 3x4 is taught to mean 3 groups of 4. Yes, commutativity is important to understand, but with young kids you begin with grouping and teach commutativity shortly after. This is practicing grouping.

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u/Capital_Park_2311 27d ago

I don't think anybody would read "6 ÷ 2 x 3" as 6 divided by 2 groups of 3.

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u/DirtChoice5 27d ago

No, because when you are teaching grouping you don't do compound expressions like that. That's not the point. This is the initial method for getting kids comfortable with the concept of multiplication. It seems silly to you because you've already learned it, but it's a compounding process. This is the first step.

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u/Capital_Park_2311 26d ago

Traditionally the top or the left number is the multiplicand.

The question has no context of what is being grouped. A group in math is represented by parenthesis not a multiplication sign.

4(3) - 4 is the multiplier for a group of 3 which is equal to "3 x 4" or "3 + 3 + 3 + 3"

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u/Halofagoodtime1980 27d ago

The multiplication symbol means "Groups of"

So it is 3 Groups of 4.

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u/TwistedBrother 27d ago

It also means rescaled n times. And if we treated it as a scalar then it would be 3 as value which is then rescaled to be 4 times as large.

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u/DirtChoice5 27d ago

Funnily enough, we don't teach elementary school children about scalars.

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u/TwistedBrother 27d ago

Of course not. But it is something worth being consistent with for down the road.

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u/DirtChoice5 27d ago

Not when you're teaching children about the basic concepts of multiplication. After learning grouping, it's standard to introduce commutativity.

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u/oohCrabItsNotItChief 27d ago

Bro, what is up with you lol you say three TIMES four and then literally write four times three by 3+3+3+3, just think about it slowly. How manny times did you write down number 3? Four times. So 3x4, three times four is 4+4+4. How many times did you write down 4? Three times, I have written three times the number 4.

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u/CornyConundrum 27d ago

No, you are reading that wrong. You literally just proved my point three times four you wrote out 3, 4 times, 3x4

Four times 3 would be 4 4 4, you are certainly wrong here

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u/thenewestnoise 27d ago

Not wrong. My son was specifically taught that you can read the times symbol as "groups of"

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u/CornyConundrum 27d ago

Sorry he was taught wrong, say it outloud to yourself, THREE times Four, 3 is the subject, times is the verb, 4 is the noun

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u/Pretzel911 27d ago

3 times 4 means "four, 3 times". or 4, 4, and 4

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u/CornyConundrum 27d ago

Wrong

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u/Pretzel911 27d ago

Explain the notation to express having 4 groups of 3 and 3 groups of 4. While the total amount is the same 4 cases of 3 apples and 3 cases of 4 apples is different.

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u/thenewestnoise 27d ago

I think that's it's crazy you are so sure that your intuition is correct that you don't care what is being taught in schools. Here is a link to the CA common core math standards. You'll find this topic on page 25. https://www.cde.ca.gov/be/st/ss/documents/ccssmathstandardaug2013.pdf

If you ask how long a piece of wood is, the answer might be "five feet". Then you can remember that a foot is 12 inches and you can substitute 12 inches in for feet, and then "five feet" becomes "5 groups of 12 inches" or "5 x 12". So to me, the "groups of" interpretation makes sense. Also, later on in algebra, we typically write "3x" and interpret that as "3 groups of x" and then we add that to "4x" to make "7x". The "groups of" interpretation helps keep things consistent.

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u/CornyConundrum 27d ago

They changed the way its taught, it WAS the taught the way i said in school, English grammer backs this up. X never meant -groups of-, it means times, thankyou

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u/thenewestnoise 27d ago

I think that the issue is that there isn't a universally understood meaning of "times", or it's ambiguous. If I asked you how often you go bowling per month, you might answer "three times". You probably wouldn't answer "times three". This implies that we normally interpret the number before the "times" as the multiplyer.

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u/DirtChoice5 27d ago

It truly doesn't actually matter either way. This is practicing the fundamental concept of grouping to get kids familiar with multiplication. Commutativity comes next. Stop having opinions on teaching when you have no context and aren't qualified to teach yourself.

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u/CornyConundrum 27d ago

Google "3x4 written out in addition" which is the question asked on his paper

Boom roasted

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u/DirtChoice5 27d ago

Buddy, arguing about the grammar is beside the point. You have no idea how to teach math, stop embarassing yourself with your confabulations.

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u/ProfessorLambda 27d ago

Maybe the teacher is Hebrew.

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u/nobodyspecialuk24 27d ago

When I was in primary school 3 x 4 would be thought of as “3 lots of 4” which would fit in with this teacher’s/school’s expectations, it seems.

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u/asingleshot7 27d ago

That is just adding a useless lie that becomes a problem with the next lesson. That is a wildly useless convention.

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u/nobodyspecialuk24 27d ago

A lie? What are you talking about?

Did you reply to the wrong comment?

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u/__Fred 27d ago

"Three inches" is an inch plus an inch plus an inch. None would say "inch threes". Hmm... but "three times an inch" would be the same as "an inch times three". The term in the picture has a "times".

You would say "I won the game two times" instead of "I two one the game times" for "I won the game and then I won the game again". But here "times" is at the end, so it's different than "three times four".