9.7 Preparing for the GMAT. In many settings, the "rules of probability" are just basic facts about percents. A company that offers courses to prepare students for the Graduate Man agement Admission Test (GMAT) has the following information ahout its customers:

20% are currently undergraduate students in business; 15% are undergraduate students in other fields of study; 60% are college graduates who are currently employed; and 5% are college graduates who are not employed.

(a) What percent of customers are currently undergraduates? Which rule of probability did you use to find the answer?

(b) What percent of customers are not undergraduate business students? Which rule of probability did you use to find the answer?