Hello! I am stuck on one part of this problem:

Suppose that X and Y have the joint pdf f_x,y(x,y)=(xy^2)/39 for the points (1,2), (1,3), (2,2), and (2,3). Find the conditional probability that X is 1 given that Y is 2.

I understand that conditional probabilities can be solved with f_x,y(x,y)/f_x(x) but I think my calculations are off. I've tried many times and the answers I've gotten were .1875 and .15 but those are not right.