A 1995 study by the School of Public Health reported that 87?% of male students who live in a fraternity house are binge drinkers. The figure for fraternity members who are not residents of a fraternity house is 71?%, while the figure for men who do not belong to a fraternity is 46?%. Suppose that 13?% of U.S. male students live in a fraternity? house, 18?% belong to a fraternity but do not live in a fraternity? house, and 69?% do not belong to a fraternity.
a. What is the probability that a randomly selected male student is a binge? drinker?
b. If a randomly selected male student is a binge? drinker, what is the probability that he lives in a fraternity? house?