If m and n are integers, is m odd?
1) n + m is odd
2) n + m = n^2 + 5
OA: B
Would anyone please help explain?
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tohellandback
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IMO B
1) n + m is odd
m can be even or odd. Not SUFF
2) n + m = n^2 + 5
n=2,m=7
n=3,m=11.
m is odd in any case.
SUFF
1) n + m is odd
m can be even or odd. Not SUFF
2) n + m = n^2 + 5
n=2,m=7
n=3,m=11.
m is odd in any case.
SUFF
The powers of two are bloody impolite!!
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ghacker
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If m and n are integers, is m odd?
1) n + m is odd : If m+n is odd m can be odd or m can be even because we don't know the value of n so this statement is insufficient
2) n + m = n^2 + 5 : We know that n and n^2 have the same parity ; that is if n is even n^2 is even and so on ....
then m = n^2-n +5 but n^2-n is always even so n^2-n+5 is always odd
Hence m is odd
1) n + m is odd : If m+n is odd m can be odd or m can be even because we don't know the value of n so this statement is insufficient
2) n + m = n^2 + 5 : We know that n and n^2 have the same parity ; that is if n is even n^2 is even and so on ....
then m = n^2-n +5 but n^2-n is always even so n^2-n+5 is always odd
Hence m is odd
