GMATPREP: Number

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GMATPREP: Number

by cubicle_bound_misfit » Sun Jun 22, 2008 6:37 pm
regards,
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by egybs » Mon Jun 23, 2008 9:49 am
Is OA, A?

The question doesn't say that k has to be an integer... It can be -.5 for example.

In which case, II would be true, but the original would not be.

If k was an integer, then I believe D would be the right answer.

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by beeparoo » Wed Jun 25, 2008 8:02 pm
I too think the OA is "A"

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by anjaligeorge1 » Thu Jun 26, 2008 5:45 am
im getting the answer as D

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oa

by ektamatta » Sun Jul 06, 2008 3:55 pm
what is OA?

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by ed09 » Sun Jul 06, 2008 4:31 pm
Hi guys,

I dare to say that the answer is A and here is my solution.

(1)
1/(k-1)>0 This inequality works only if k-1>0 or k>1
If k>1, than 1/k>0 is always true.
SUFFICIENT

(2)
1/(k+1)>0 This inequality works only if k+1>0 or k>-1
That is, despite k is neither 1, or -1, nor 0, it still can be negative or positive. This ambiguity of k's sign doesn't let us to be sure of the sign of 1/k. Therefore this statement is INSUFFICIENT.

A is the answer.

Hey, Cubicle Bound Misfit, won't you, plaese, make OA public, finally!
Enough of that keeping folks in suspense! :)

Best!

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by cubicle_bound_misfit » Wed Jul 09, 2008 10:07 pm
Sure ED09,
Just a few days before Joker reaches Gotham city let me unveil to you that the OA is A :wink:
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