Integer question

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Integer question

by Baldini » Thu Mar 05, 2009 6:43 am
If n is an integer between 2 and 100 and if n is also the square of an integer, what is the value of n?

(1) n is even
(2) the cube root of n is an integer

OA is B

Could someone kindly explain the answer and the reasoning behind it? I got OA E
thanks
GMAX
Source: — Data Sufficiency |

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by avenus » Thu Mar 05, 2009 7:28 am
(1) possible values for n: 4, 16, 36... Not sufficient

(2) n has to be the square of an integer AND the cube of an integer i.e., an integer to the power of 6. The only integer between 2 and 100 that complies with this is 2^6 = 64 (the next one would be 3^6= 729), so SUFFICIENT

Does that help??

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by Baldini » Thu Mar 05, 2009 7:44 am
yep, thanks a lot, much better explanation than in the book!
GMAX