# At Jefferson Middle School, 12% of the students play volleyball and 5% of the students play volleyball and basketball. What is the probability that a student that he plays volleyball?

This one might be misleading so I will start with assumptions. If 12% play volleyball and 5% play both volleyball and basketball then I assume that this is two mutually exclusive groups thus the total of 12 and 5 we know play volleyball. If not then p(a or b) =p(a)+p(b)-p(a)×p(b) =.5+.12-.06 = .11. In fact it's not mutually exclusive.