Intergers- DS

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Intergers- DS

by rabab » Wed Oct 01, 2008 8:21 am
If n and k are positive integers, is n/k an even integer?

1. n is divisible by 8
2. k is divisible by 4.

IOM it's C.

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by gdrea3 » Wed Oct 01, 2008 8:26 am
The answer should be E

First off, neither statements are sufficent alone b/c each provides info about one of the variables.

Putting the statments together--pick multiples of 8 for n and 4 for k:
n=8, 16, 24, 32, 40, 48 etc.
k=4, 8, 12, 16, 20, 24, 28, etc.

So, put the statements together:
-If n=8 and k=4-->2-->even
-If n=8 and k=8-->1-->odd
INSUFFICIENT. Choice E.

Or, without writing out any of the multiples, you can just say that there are too many possible scenarios for n and k where some quotients are even and some are odd, so together but statements are insufficient. :D

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by rabab » Wed Oct 01, 2008 9:53 am
Thanks mate! That was easy :)

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by sumithshah » Thu Oct 02, 2008 4:46 am
Another algebraic way of doing it ( if you are like me and dont trust your skill to pick good numbers )

n=8(i) , where I is an integer
k = 4(j), where j is an integer

Note : I and J can be even or odd.

So, n/k = 2(i)/j

If J is 2 and I = 3, then odd. If i=3, j=3, then even. Hence E