If (2^x)(3^y) = 432, where x and y are positive integers, then (2^x-1)(3^y-2) equals:
Choices:
A) 16
B) 24
C) 48
D) 96
E) 144
So I would start attacking this problem by quickly performing the prime factorization of 288. With that it is easy to count the 5 twos and the 2 threes that are the prime factors. So x=4, y=3. now quickly 2^3(3^1)=24. Than answer should be number 2.   24
<result>B</result>
If (2^x)(3^y) = 432, where x and y are positive integers, then (2^x-1)(3^y-2) equals: