Divisible qn

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Source: — Data Sufficiency |

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Re: Divisible qn

by KICKGMATASS123 » Tue Nov 10, 2009 6:30 pm
hariharakarthi wrote:Is positive integer n is divisible by 4?
1. n^2 is divisible by 8
2.sqrt(n) is an even integer.

NOt so sure about this one?

Is it C?

Let me know then i'll explain

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Re: Divisible qn

by palvarez » Tue Nov 10, 2009 8:48 pm
hariharakarthi wrote:Is positive integer n is divisible by 4?
1. n^2 is divisible by 8
2.sqrt(n) is an even integer.
2^3 divides n^2, therefore, 2^2 divides n.
n = even^2 = multiple of 4.

D is the answer

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D

by brick2009 » Tue Nov 10, 2009 8:59 pm
a.) n^2 /8 ...only numbers that are divisible by 8 are also divisible by 4.....AD

b.) sqrt(n) = even
==> n = even^2
try any even number, it is divisible by 4..B


--D