61 even/odd

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by GMATBootcamp » Sun Oct 04, 2009 12:32 am
ans should be B

statement 1: insufficient information because even if m is even, n could be either even or odd, which would affect the outcome of m+n

statement 2: sufficient information because n^2 is even if n is even and n^2 is odd if n is odd. The fact that "-m is even" tells us that m has to be the same even/odd as variable n. If n can be either even or odd, and m has to be the same even/odd as n, then it doesn't matter if n is either even or odd because m+n will always be even.
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Re: 61 even/odd

by umaa » Sun Oct 04, 2009 7:17 am
ern5231 wrote:Is m+n even?
1) m is even
2) n^2-m is even
IMO C.

Statement 1 is not sufficient since we don't know whether n is odd or even.

n^2-m: n and m both might be odd or even

When combining, we'll get n and m both are even.


OA pls/
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by ern5231 » Thu Oct 08, 2009 8:22 pm
OA is B