Simple question divides the internet

Divide 40 by 1/2 and add 15. What do you get? This simple question somehow manages to confuse both humans and computers.

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[WillRennar]

Some people see "divide by 1/2, " think "divide in half, " and go the wrong way. Mystery solved.

[ImperfectVD]

Here's a rule of thumb. If your answers to "divide 40 by 1/2" and "multiply 40 by 1/2" are the same, then you should rethink how you're interpreting the question.

[icefreezer]

40 ÷(1/2) + 15 = 40 × 2 +15=95
No perspectives needed

[karhukivi]

When one accepts that 1/2 = 0.5 the solution is obvious.

[hwcamaro]

It's more of a reading comprehension question rather than a math problem.

[davidwiley]

This is not a math problem. It's an English language problem.

[jdizzle]

Yeah, it’s all semantics until you need to keep a plane in the air.

[Purpose_Porpoise]

It's like cell division. You divide a cell into halves and end up with 2 cells.

Do that with 40 cells, and you end up with 80. Add 15, and you end up with 95 cells.

[keith]

This is why whenever a contract has some kind of calculation in it, before you agree to it you make sure you know exactly what the other party thinks the calculation means.

[joncross]

If they wanted you to divide in half they would say Divide by two, but since they said by 1/2 and not in 1/2 its different. Easy mistake to make.

[MLWJ]

This is not a math problem at all, it's a bit of an ambiguous language problem...

[Nic_La]

Breaking news: Using wrong notation confuses people.
Thats why you use math notation. Not a sentence in english.

[ytdertignulses]

An example of what I have commented on for many years; a lot of maths questions are actually language comprehension issues. If questions were written unambiguously it would cause less stress to people.

[LRick]

Many people can't do fractions.
This is what I do in my head:
40/0.5=80+15=95
Everything else is just incorrect.

[llcn]

2:47 based on how the question is written, shouldn’t it technically be (40/(1/2)) + 15 in google?

[MusicForLifw]

Here's a simple explanation, As we learnt Rational No.'s, for divison, the rule is "KEEP, CHANGE, & FLIP", if you take 40 ÷ 1/2, You KEEP the 40, you CHANGE the sign (divison changes into multiplication), and then you flip the 1/2 ( take the reciprocal of 1/2 and you get 2/1. Now put everything together - 40 x 2 = 80
then as the problem goes 80 + 15 = 95
DONE! its a very simple problem if you keep it right.

btw Love you videos MindYourDecisions ❤

[MyrkDomolith]

Worth clarifying: the original question in this argument had "by half, " not "by one half" or "by 1/2" or its variants.
Lots of room for misunderstanding.

[MrValdesbg]

Instantly got 95 before the video even started. How is it possible people get this wrong. That's basic math taught in 4th grade.

[TheLobsterCopter]

Imagine seeing "divide by 1/2", and interpreting it as "multiply by 1/2"...

[amirtahaabbasi]

I mean, this isn't mathematics
This is the unknowledged "grammer of both mathematics and English "
.
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