Tactic sum

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Tactic sum

by ruplun » Thu Jul 28, 2011 8:49 pm
If n^4 is divisible by 32, what would be the remainder if n is divided by 32?

a. 2
b. 3
c. 4
d. 5
e. 6
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by ColumbiaVC » Thu Jul 28, 2011 9:04 pm

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by Anurag@Gurome » Thu Jul 28, 2011 9:30 pm
ruplun wrote:If n^4 is divisible by 32, what would be the remainder if n is divided by 32?

a. 2
b. 3
c. 4
d. 5
e. 6
n^4 is divisible by 32 or 2^5 implies n^4 = (2^5)k, where k is any constant.
Now, n will be the least when k = 2^3
So, n^4 will be divisible by 2^8, which implies n will be divisible by 4.

Now since n is divisible by 4, it will leave only multiples of 4 as remainder, when divided by 32. And in the given answer choices, only choice C is a multiple of 4.

The correct answer is C.
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