2) DS a/b terminating decimal?

[ern5231]

2) a, b are positive integers. Does a / b have a terminating decimal?
1> a = 5 ^ r, r is some positive integer
2> b = 2 ^ s, s is some positive integer

[beat_gmat_09]

2) a, b are positive integers. Does a / b have a terminating decimal?
1> a = 5 ^ r, r is some positive integer
2> b = 2 ^ s, s is some positive integer

IMO D

A - alone is not sufficient because denominator is not known.
B - not suff because numerator is not known.

combine A & B take r and s as any +ve numbers the result will always terminate.

[liferocks]

My take is ans B

fraction with the lowest denominator of 2 or 5 or their power will always terminate as they are factors of 10

option 2 says the the denominator is 2^s hence sufficient but option 1 does not say anything about the denominator.Hence not sufficient

[ern5231]

OA is B