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Question

please explain this ..i dont have the OA.

yezz · Answer

if m is prime 

then highet divisor might be either m or 1 given that n is not prime and n is a multiple of m...............insuff

from 2

m = 2/7n,,,,,,,,,n is a mutliple of 7 and m is even........insuff

both

m = 2 and n = 7x.........insuff, devisor could be 1 or 2.

I say E

Balvinder · Answer

From A and B together

A says m is prime....2, 3, 5, 7


from B m = 2n/7

B says m Even so only number for m can be 2
and n =7

so GCD can be 1

Is it Ok or am i missing something?

trivikram · Answer

Longtime welcome back

GMAT TIGER · Answer

You are ok. it should be C since m is a prime and 2n = 7m, the common divisor is 1.

GMATBLACKBELT · Answer

Stem is asking for GCF of N and M. Also important to note that N and M are integers.

S1: M= prime #, no help.

S2: 2N=7M --> N=7/2M Since N is an integer M MUST be divisible by 2. The opposite is true for N, b/c M=2N/7 N must be divisble by 7.

However, as u can see N and M can be anything so long as they fit this criteria. Insuff.

B/c M is prime and must be divisible by 2, then M must be 2. 

So N=7. GCF is 1.


C

yezz · Answer

Hi Trivi :-D been a long time , i was reallocated to another country and i had to put my MBA plans on hold for a while. Guys You are right n = 7 , the moral is ..........never try to solve tricky GMAT late at night after working for 14 hours.

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