In the graduatingclass of a certain college, 48 percent of the students are male and 52 percentare female. In this class 40 percent ofthe male and 20 percent of the female students are 25 years old or older. If one student in the graduating class israndomly selected, approximately what is the probability that he or she will beless than 25 years old?
0.90
0.70
0.45
0.30
0.25
前面是25 years old or older,问的是less than 25 years old!