If x and y are positive integers such that the greatest common factor of x2y2 and xy3 is 45, then which of the following could y equal?
The correct answer is E.
The greatest common factor of x2y2 and xy3 is xy2, which equals 45.
Because x and y are both positive integers and 45 = 325, there are two possibilities for x, 5 or 45.
If x is 45, then y is 1. If x is 5, then y = 3. Thus, 3 is the answer choice.