Bounce1987 wrote:

If a, b are positive integers, what is the value of b?

(1) \(2^a7^b=1,372\)

(2) a=2

Hi..

It is given that a and B are POSITIVE integers..

Statement I

\(2^a7^b=1372.....\)

Clearly sufficient as a and b will have unique values as 2 and 7 are co-prime.

Still if you were to find value of b, it is to realise that 1372=1400-28=14*100-14*2=14(100-2)=14*98=2*7*2*49=2^2*7^3..

b is 3..

Statement II..

Only a given

Insufficient

A

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1) Absolute modulus : http://gmatclub.com/forum/absolute-modulus-a-better-understanding-210849.html#p1622372

2)Combination of similar and dissimilar things : http://gmatclub.com/forum/topic215915.html

3) effects of arithmetic operations : https://gmatclub.com/forum/effects-of-arithmetic-operations-on-fractions-269413.html

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