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by ankurmit » Sun Jul 18, 2010 11:06 pm
If m and n are nonzero integers, is m/n an integer?

(1) 2m is divisible by n

(2) m is divisible by 2n

I want to know concept behind this
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Ankur mittal
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by 4GMAT_Mumbai » Sun Jul 18, 2010 11:14 pm
Hi,

The concept behind this is that if a is divisible by b then, a can be expressed as 'b times some other integer'

a = b * p where p is also an integer.

Stmt 1:

2m is divisible by n.

So, 2m = n * p.

Here, m / n = p / 2. Now, we only know that p is an integer. p/2 may or may not be an integer. Hence, not sufficient.

Stmt 2:

m is divisible by 2n.

So, m = 2n * q; where q is some integer.

Here, m / n = 2 * q. If q itself is an integer, 2q will definitely be an integer. Hence, sufficient.

Hope this helps. Thanks.
Naveenan Ramachandran
4GMAT, Dadar(W) & Ghatkopar(W), Mumbai

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by ankurmit » Mon Jul 19, 2010 1:30 am
Thanks naveenan :)
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