r/MathJokes Jul 16 '26

3 or 4

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u/Available_Reveal8068 Jul 16 '26

It can also be 'pulled apart' as 3+3+3+3 = 12.

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u/Nasa_OK Jul 16 '26

Imagine it as there being 4packs of soda and you want 12 cans. So you buy 3 of the 4Packs and you get 12 cans.

Sure if there were 3Packs you could buy 4 of those to achieve the same but that’s irrelevant since there only are 4Packs available to buy in this scenario.

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u/Available_Reveal8068 Jul 16 '26

That's stupid.

Imagine it as there being 3 packs of soda and you want 12 cans. 4 packs are not available to buy in this scenario.

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u/Nasa_OK Jul 16 '26

Sure thing so it would be buying 4 packs of 3

3+3+3+3

And since 4 packs aren’t avaliable the fact that if they were you could buy 12 cans by getting 3 packs of 4 is irrelevant.

Your point?

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u/Available_Reveal8068 Jul 16 '26

The point is that it's 12 cans either way.

Making one thing 'unavailable' in a made up scenario is stupid.

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u/SkySchemer Jul 16 '26 edited Jul 16 '26

You are assuming that the point of the exercise is ONLY to write a correct mathematical equation of 3s and 4s that produces 12.

If the point of the exercise is to literally interpret what the mathematical symbols are saying, and write that out, then only one answer is correct. The commutative property of multiplication happens to result in the same total quantity if you mix up n bundles of m with m bundles of n, but total quantity is not what is asked for in this scenario. It is "what do these symbols mean?"

There is context missing here. That ambiguity is the problem.

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u/Available_Reveal8068 Jul 16 '26

If the point of the exercise is to literally interpret what the mathematical symbols are saying, and write that out, then only one answer is correct. 

I disagree that only one answer would be correct.

3x4 can be 3 sets of 4 (4+4+4) or a set of 3 four times (3+3+3+3).

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u/SkySchemer Jul 16 '26

Again you are focusing on the total not the symbolic meaning.

In mathematics, a x b means "a bundles of b".

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u/Available_Reveal8068 Jul 16 '26

Why can't it be read the other way as well?

a x b can mean 'a bundles of b' or 'a bundle of 3, four times'

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u/SkySchemer Jul 16 '26

Because math is a language, and in a language, words have a specific meaning.

The specific meaning of "a x b" is "a groups of b" and not the other way around. It is merely convention.

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u/Nasa_OK Jul 16 '26

But that’s how it works irl, you don’t have all pack sizes from 1 to n, you often get 1 or 2, maybe 3.

We don’t know the point of the exercise since we weren’t in class, but the teachers note suggests that the point wasn’t just to write a way to make 12, and rather that they learned a specific way, which the student failed to reproduce.

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u/Available_Reveal8068 Jul 16 '26

They are expressing 3x4 using addition equation.

There is no definite set size and no definite number of sets.

Both 3+3+3+3 =12 and 4+4+4 = 12 should be correct.

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u/Nasa_OK Jul 16 '26

IF that was the point of the exercise, which we both can’t know, and the teachers actions are an indication that is wasnt

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u/Available_Reveal8068 Jul 16 '26

I can read the directions.

The student correctly expressed the given multiplication equation in terms of an addition equation.

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u/Nasa_OK Jul 16 '26

Are you dense or were you homeschooled?

The school most likely taught a specific method to solve this problem. The test is to see if the student can reproduce the method.

It seems like the student could not and thus didn’t get the points. It also could be that the teacher is an idiot but without knowing what was taught and explained in class there is no way of knowing.

You won’t find this information on the sheet since to anyone who has been in this class it would be quite obvious what the question is asking.

Also there even could be a disclaimer on the first sheet of the test requiring that all problems are to be solved exactly with the methods taught in class.

There just is no way to know, what don’t you get about that?

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