GMAT prep DS question

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Source: — Data Sufficiency |

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Re: GMAT prep DS question

by parallel_chase » Sat Jul 19, 2008 3:00 pm
mlane25269 wrote:Can someone explain? Thanks!
You can set-up the equation as n=25k+13, k is a constant.

Statement I
n<100

25(1)+13 = 38
25(2)+13 = 63
25(3)+13 = 88

Not Sufficient.

Statement II

n = 20k+3

if we compare this equation with the equation in the question stem

n = 20(3)+3 = 63
n = 25(2)+13 =63

but we also have to consider the other possibilities as well.

n=20(8)+3 = 163
n=25(6)+13 = 163

Therefore, Not sufficient.

Statement I & II

n=25k+13 & n<100 & n=20k+3

Only answer that satisfies all the above conditions is 63.

Hence C.