im no pro like some ppl on here...but gmat is in 10 days..so let me give it a shot..
break down 4^17 - 2^28
to (2^17)2^17) - 2^28
= 2^34 - 2^28
= 2^28(2^6 - 1)
= 2^28 (63)
Break down 63 into the prime factorization and you get 7 as the highest prime...7 X 3^2..
hence 7...
hope i am correct...
prime factor
This topic has expert replies
Source: Beat The GMAT — Problem Solving |












