in a sample of 275 students, 20 say they are vegetar- ians. of the vegetarians, 9 eat both fish and eggs, 3 eat eggs but not fish, and 7 eat neither. choose one of the vegetarians at random. what is the probability that the chosen student eats fish or eggs? (a) 9/20 (c) 22/20 (e) 22/275 (b) 13/20 (d) 9/275