Suppose that a certain college class contains 55 students. Of these, 30 are seniors, 28 are mathematics majors, and 7 are neither. A student is selected at random from the class. (a) What is the probability that the student is both a senior and a mathematics major? (b) Given that the student selected is a mathematics major, what is the probability that she is also a senior? Write your responses as fractions. (If necessary, consult a list of formulas.) (a) 10 (b) [ X