Positive prime numbers

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Positive prime numbers

by gmat009 » Tue Oct 07, 2008 9:12 pm
if p, s, and t are positive prime numbers, what is the value of p^3s^3t^3?
(1) p^3st=728
(2) t=13

OA is A

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Re: Positive prime numbers

by Morgoth » Wed Oct 08, 2008 1:03 am
gmat009 wrote:if p, s, and t are positive prime numbers, what is the value of p^3s^3t^3?
(1) p^3st=728
(2) t=13

OA is A
statement (1)

728 = 2^3 * 7 * 13

either s = 7 and t=13 or s=13 and t=7

it does not matter which the value of p^3s^3t^3 will remain the same.
Sufficient.

statement (2)
t=13

we dont know anything about p or s. Insufficient.

Thus, A.