Interesting GMATFix Problem-43

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Interesting GMATFix Problem-43

by arora007 » Mon Oct 04, 2010 4:20 am
If k is a positive integer, what is the remainder when (k^2 - 4) is divided by 12?
1) k is even
2) k is ot divisible by 3
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Source: — Data Sufficiency |

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by Rahul@gurome » Mon Oct 04, 2010 5:12 am
(1) If k = 4, then remainder is 0.
If k = 6, then remainder is 8.
No unique value.
So, (1) is NOT SUFFICIENT.

(2) If k = 4, then remainder is 0.
If k = 7, then remainder is 9.
No unique value.
So, (2) is NOT SUFFICIENT.

Combining (1) and (2), If k = 8, 10, 14... (Even integers not divisible by 3) then remainder is 0.

[spoiler]The correct answer is (C).[/spoiler]
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by taneja.niks » Tue Oct 05, 2010 1:00 am
Rahul nice explanation could u plz tell me one thing as the st-1 says tht it is even why dnt we consider options as 2 is tht bcoz the K^2-4 =0

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by arora007 » Tue Oct 05, 2010 6:40 am
OA is indeed C
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