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Ned Yeung | 1 years ago (raw) | export | reply | flag 
 Okay, so seems that the debate on this is a generational thing. The meme is backwards because it's the grey-haired guy who should be saying 1, not the younger women.

Basically, if you were taught older conventions like I was (being an old fart), you would divide the 6 by the product of everything to the right of the division, because you would treat the ÷ as a /, and treat the product as a denominator.

We used to treat ÷ as an easier way to write out a fraction problem, but that is no longer.

https://cdn.mastdn.ca/media_attachments/files/111/059/082/061/958/392/original/75a1a1dad4eec5e7.png

https://cdn.mastdn.ca/media_attachments/files/111/059/111/492/400/005/original/af338b53dd30570c.png
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Ned Yeung | 1 years ago (raw) | root | parent | reply | flag 
 So in short the real answer is 9, but if you're anywhere near half a century old and haven't kept up with new changes in math, then you would get 1.
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e58edf7d | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 This relatively common category of ambiguous mathematical statements seems to ignore the use of parentheses to remove ambiguity. I suppose not using parentheses is required in order to cultivate disagreement, but I don't really see the point. It's easy to make the statement unambiguous.
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jerrymacgp | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 1) Everything in parentheses is calculated first: 1 + 2 = 3, reducing the expression to 6 divided by 2 times 3.
2) The convention for order if operations is multiplication & division are at equivalent hierarchical levels & so are calculated in order left-to-right, so 6 divided by 2 = 3.
3) A number preceding parentheses without an operation symbol is multiplication. So then it’s just 3 x 3 = 9.
The correct answer is 9. QED.
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Welbog | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 I was curious, so I found my uni textbook. Here it is using solidus (/) instead of obelus (÷) but the result is clearly everything to the right of the symbol is grouped (it would be the denominator in fractional notation). The same is true of the units. (Specifically the Permittivity of free space). This is Physics (5th ed.) by Serway & Beichner, printed 2000.

https://cdn.mastdn.ca/media_attachments/files/111/059/458/458/564/156/original/d5403580874b3f47.jpg
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藤井太洋, Taiyo Fujii | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 9 must be right answer, but if as following?

solve 6 ÷ 2x, x = 1 + 2

It might be 1
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Paul Turnbull | 1 years ago (raw) | root | parent | reply | flag 
 @b541bfe5 While I will admit my first instinct was 1 the fact of the matter is the statement is not ambiguous and the answer is 9. Brackets first then multiplication and division going left to right. Shorthand notation doesn’t change the rules. I use a calculator called Soulver that allows entering equations and for it `6/2(1+2)` equaled 9.