Collecting cereal boxes Geno goes to the Price Chopper and f

Collecting cereal boxes Geno goes to the Price Chopper and finds that Wheaties is placing pictures of UConn women’s basketball players inside its cereal boxes. A total of 6 players are featured, each appearing with equal probability. (a) Find the expected number of boxes Geno needs to buy in order to obtatin pictures of three different players. Explain your reasoning. (b) Let N denote the number of players that Geno has collected after buying 10 boxes. Find E[N]. [Hint: It is easier to find E[M], where M = 6 N, the number of players not collected.]

Solution

a)

1 * 1/6 + 2 * 1/6 + 3 * 1/6

expected value : 1