DS GMAT PREP

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Source: — Data Sufficiency |

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Re: DS GMAT PREP

by mridula » Fri Nov 13, 2009 12:18 pm
kartik1979 wrote:hi , can someone help how to arrive at a solution in the below sum
IMO B.

n^3 will be an Integer.
n^3 = 450*y
=(3^2)*(5^2)*2*y.
for n^3 to be a perfect cube, y must have two 2s, one 3 and one 5 as factors.

Therefore, I think y/[3*(2^2)*5] MUST be an Integer. Hence, the answer is B.

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by heshamelaziry » Fri Nov 13, 2009 12:55 pm
According to your break down of the factors of y, which In agree with, answer should be A