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Source: — Data Sufficiency |
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by cramya » Sun Feb 22, 2009 9:16 pm
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by sureshbala » Sun Feb 22, 2009 10:42 pm
Given n = 3k+2
and t = 5p+3

So nt = 15kp+9k+10p+6.

Since 15kp is divisible by 15, in order to give the remainder when nt is divided by 15, we need information about k and p.

Statement I: n-2 = 3k is divisible by 5. So k is divisible by 5. From this we can conclude that 9k is divisible by 15. But we don't know about p.

So I is not sufficient

Statement II: t =5p+3 is divisible by 3, which means p is divisible by 3 So we can conclude that 10p is divisible by 15. But we don't know about k.

So II is not sufficient

Combining both, we can conclude that both 9k and 10p are divisible by 15, hence the remainder when nt is divided by 15 is 6.

Hence C is the answer
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by naaga » Mon Feb 23, 2009 4:29 am
The answer is C
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