Got one from GMATPrep

n is an integer >0 r is remainder when n^2-1 div by 24. What is r ?

1. n not div by 2
2. n not div by 3

OA = both (c)

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n^2-1=24t+r
r=n^2-1-24t

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n<>2k
n<>3k how to proceed

Confusing DS - need the right approach

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With statement 1 alone, wouldn't n=3 and n=6 be possible? 1/3 = 0.3333333333.... 1/6 = 0.1666666666.... Although the first decimal digit in 1/6 is 1 the rest of the decimal digits are all 6's and thus, the 10th decimal digit would also be 6. With statement 2 alone, it seems to me that nothing new h...