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Ryan91
29-04-2011, 12:51 AM
It's a simple mathematical puzzle, please tell me what answer you get for this question:

6÷2(1+2)=?

brianmc
29-04-2011, 02:30 AM
9??
What do i win?

Peevemor
29-04-2011, 05:58 AM
1?

Sylar
29-04-2011, 08:47 AM
1?

:agree: - Always multiply out the brackets first.

Wish the equations I dealt with on a day to day basis were as simple as that again :greengrin

brianmc
29-04-2011, 08:49 AM
Ach its been twenty years+ since i last did an equation.

PeeJay
29-04-2011, 09:20 AM
First up - thanks for taking my mind off this awful wedding with this little brain jog.

Seems the answer is indeed 1

Marabou Stork
29-04-2011, 11:09 AM
BODMAS.

The answer is indeed 1.

CropleyWasGod
29-04-2011, 11:11 AM
BODMAS.

The answer is indeed 1.

The answer would be 1, if there were a "/" before the brackets, no?.

I reckon the answer is 9. 3 x 3.

Peevemor
29-04-2011, 11:23 AM
The answer would be 1, if there were a "/" before the brackets, no?.

I reckon the answer is 9. 3 x 3.

The answer would be 9 if it had been written as 6÷2 x (1+2)=?, otherwise the 2(1+2) part is treated as a single entity, ie. 6.

CropleyWasGod
29-04-2011, 11:27 AM
The answer would be 9 if it had been written as 6÷2 x (1+2)=?, otherwise the 2(1+2) part is treated as a single entity, ie. 6.

Not convinced, but then it's been a while :greengrin

B(rackets) = 3
O(f) n/a
D(ivide) = 3
M(ultiply) = 3(3) , ie 9

A(dd) n/a
S(ubtract) n/a

--------
29-04-2011, 12:09 PM
The answer's 1 unless my maths teacher was telling me lies.

Ryan91
29-04-2011, 05:34 PM
to put your mind at rest the answer is in fact one (1)!

When written out in an algebraic fashion, the 2(1+2) is treated as a single entity and thus must be dealt with first.

brianmc
29-04-2011, 06:53 PM
I went with 6÷2. 3
(1+2) 3
Gives you. 3x3. Hence my seemingly daft answer of 9

SRHibs
30-04-2011, 02:36 PM
Parenthesis
Exponents
Multiplication
Division
Addition
Subtraction

danhibees1875
01-05-2011, 01:26 AM
Initally I thought it was 1 - after seeing on a facebook poll that over half thought the answer was 9 I investigated and it turns out it is 9. Something to do with multiplying before you divide :confused:

Here is what was said:

I am your college professor that you requested, with a doctorate in Mathematics. I will break this down as simply as possible and end this debate as approx. 10 students have already asked me this today.
The problem as it is written is 6÷2(1+2) , the ÷ cannot be substituted with a fraction bar because they have different ranks on the order of operations. It is an illegal math move to do this. The bar ranks with parentheses, ÷ is interchangeable with *. therefore the problem must be solved as 6÷2(1+2) NOT 6 (over) 2(1+2) we do the parentheses first, so 6÷2(3), the parentheses are now no longer relevant, because the number inside is in it's simplest form. Every single number has implied parentheses around it.
6÷2(3)
(6) ÷(2)(3)
6÷2*3,
or even converting the division to multiplication by a reciprocal (a legal math move)
(6)(1 (over) 2)(3)
are all correct ways to write this problem and mean exactly the same thing. Using pemdas, where md and as are interchangeable, we work from left to right, so (3)(3) or
3*3= 9

Just because something is implied rather than written does not give it any special rank in the order of operations.

The problem in it's simplest form, with nothing implied would look like this:
(1+1+1+1+1+1 (over) 1) ÷ (1+1 (over) 1) * ((1(over) 1) + (1+1 (over) 1))
From here, nothing is implied, This again, works out to 9.

If the symbol '/' was used this whole debate would be ambiguous since that symbol can mean "to divide by" or it could mean a fraction bar.

HOWEVER, because the ÷ symbol is used, it can not be changed to mean a fraction bar because that would change the order of operations and thus the whole problem, you can't change a symbol to mean something because you want to, in doing so you are changing the problem.

Once and for all, the answer is 9.

Hopefully some of my students see this so I can stop answering this question.

End of debate... hopefully.

Although perhaps its just written in an ambiguous way and has 2 answers. :greengrin

Dibben
01-05-2011, 05:13 PM
I came up with the answer 9, even before I read the post above!

lyonhibs
02-05-2011, 11:04 PM
This
Type
Of
S***
Is
Exactly
Why
I
Dingied
Maths
ASAP

A wee acronym for y'all to memorise and use, like, about as often as I use BODMAS, or SOHCAHTOA etc etc :greengrin