Q. A box contains three blue marbles, five red marbles, and four white marbles. If one marble is drawn at random, find: a) P(blue|not white) b) P(not red|not white) The answer for both a) and b) is 3/8. However right now I don't even understand the question. part a) wants possibility of getting a blue ball given that white wasn't drawn. So... NOT getting a white ball is 8/12. Given that, getting a blue ball is 3/11. but 3/11 is not even close to 3/8! What's wrong with my work? Thanks in advance!