Gmatprep exponents

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Gmatprep exponents

by maolivie » Thu Jul 05, 2007 5:46 pm
(2^(4-1)^2)/(2^(3-2))

1- 2^8
2- 2^7
3-2^6
4-2^5
2-2^4

I keep getting 2^6, OA is 2^8, can someone please clarify or let me know what I am doing wrong. PEMDAS right?

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by thumpin_termis » Thu Jul 05, 2007 6:11 pm
The main point here is that:

2^3^2 is NOT equal to (2^3)^2


1. 2^3^2 = 2^9
2. (2^3)^2 = 2^6

If you see that, then it's

(2^3^2) / 2^1 = 2^9 / 2 = 2^8

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by maolivie » Thu Jul 05, 2007 6:23 pm
ahh interesting, I didn't see that at first.

Thanks.