What's the answer?

[Newportnobby]

This seems to be doing the rounds at the moment. There are 2 correct answers depending on your method.

8 ÷ 2(2 + 2) = ?

[ntpntpntp]

Answer = 1,  but it depends on whether you were taught to apply operator priority (BODMAS or similar acronym).   There are always loads of these questions going round the internet.    The world needs to be consistent!

[themadhippy]

Answer = 1,

thats the old answer ,the modern day answer is 16, so  to be safe my answer is  7.5

[Newportnobby]

From what I was taught in skool my answer was 1

[chrism]

It must be 42 - since that's the answer to life, the universe and everything 

[ntpntpntp]

From what I was taught in skool my answer was 1

Yes indeed.   Trouble is people use calculators these days which take in and evaluate the expression in a linear fashion, unless you use a posh scientific calculator which accepts the entire expression before parsing and evaluating it.

To avoid ambiguity the expression really requires additional parentheses (and ideally additional operators) to clarify the required operator priority instead of relying on conventions

8 / (2 x (2 + 2 )) = 1
(8 / 2) x (2 + 2) = 16

Crazy, isn't it?!  When I'm writing software to a specification I do sometimes have to insist the writer of the spec clarifies their formula/expressions to avoid such ambiguity.

[PaulCheffus]

This seems to be doing the rounds at the moment. There are 2 correct answers depending on your method.

8 ÷ 2(2 + 2) = ?

Hi

I get 16 using BODMAS

Expression in brackets first
2 + 2 = 4
Division next as it is the next operation in left to right order
8 / 2 = 4
Leaving
4 * 4 = 16

It would only be 1 if the formula was written 8/(2(2+2)

Cheers

Paul

[njee20]

I was also taught BODMAS in school (in the early 2000s), so to apply that literally (ie division before multiplication) I'd do:

(2 + 2 ) then (8/2), and multiply = 16

Americans seem to be taught PEMDAS (parenthesis, exponents, multiplication, division, addition, subtraction), which clearly reverses multiplication and division anyway, so following that I can see you could do:

2*(2+2), then divide that by 8 = 1

Google reckons 16.

All these things show you is that you need to be clear when writing equations!

Edit: cross posted with Paul, who's saying the same thing!

[dannyboy]

All you lot that were taught BODMAS and/or PEMDAS must have gone to posh schools - I was taught rithmatic! And anyway, I was wondering why there wasn't an operator before the first bracket!

[njee20]

Doesn't need to be, it's implicit that that means multiply.

[emjaybee]

All you lot that were taught BODMAS and/or PEMDAS must have gone to posh schools - I was taught rithmatic! And anyway, I was wondering why there wasn't an operator before the first bracket!

This doesn't happen often, but I agree with you. They ought to learn how to write equations correctly.

[dannyboy]

See, I said some of you must have gone to posh schools.  . Who decided that if there is no operator, you should insert a multiplication sign! Nobody told me that. 

[themadhippy]

posh skool ? the only bits of mafs i  remember  woz          B4I√u ru/16 and 2 (4/3 pi R^3)

[Mr Sprue]

Noooo it means you have an 8' layout ÷ 2 up 2 down track = 8 loco's running simultaneously! 

[Bob Tidbury]

Know wonder the country is in such a mess with finances if you can get two or three different answers to the same mathimatical question .
I give up on on this posh stuff like BODMAS etc etc .Know wonder those that went to posh schools usualy end with posh jobs it's because they can fiddle the books by useing all these different methods .

Bob Tidbury