In the World Series for baseball, the series is concluded when one team has won 4 games. Let p be the probability of team A winning a single game and assume that this probability remains constant in the series. Show that the probabilities of the series ending in 4, 5, 6, or 7 games are 0.125, 0.25, 0.3125, 0.3125, respectively, when p = ½ and 0.21, 0.30, 0.27, 0.22, respectively, when p = 2/3.