Did this on the GMATprep - and I swear I got it right, but

Question

Did this on the GMATprep - and I swear I got it right, but the original answer suggests differently.

2^(4-1)^2 / 2^(3-2)

A. 2^8
B. 2^7
C. 2^6
D. 2^5
E. 2^4

I'm convinced that my answer is   D   (highlight to see)

But the OA is   A   (highlight to see)...

bkk145 · Answer

You can think of this two way, which are totally different. Let's just consider the top part...
2^(4-1)^2
This can be seen as: (2^3)^2 = 2^6
OR
2^(3^2) = 2^9
The latter will give you the right answer. I imagine in GMATprep, it should be pretty clear. Do you have a snapshot of the problem?

Big-O · Answer

Here is the screenshot (I haven't been around enough to directly hotlink

A^B^C is the same as A^BC, therefore the top gives 2^6, not 2^9...

KillerSquirrel · Answer

edited post

Its a simple case of BEDMAS https://www.answers.com/BEDMAS 2^3^2 = 2^(3^2) = 512 not (2^3)^2 = 64 Don't check this in Excel spreadsheet. Excel will yield 64 for 2^3^2 this is wrong ! :-D

bkk145 · Answer

Thanks for the shot. I would have get 2^9 for the top, but I agree it is a bit unclear.

KillerSquirrel · Answer

see edited post above ! :-D

bkk145 · Answer

I see the operation of (4-1)^2 = 9 first.
Otherwise, I feel that there should have been parenthesizes like this:
(2^(4-1))^2

Did this on the GMATprep - and I swear I got it right, but

What do you think the answer is?

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