Ben and Jerry play a series of games of checkers. During each game each player bets a $1, and whoever wins the game gets the $2. Ben is a better player than Jerry and has a probability 0.6 of winning each game. Initially Ben had $9, while Jerry had $6, and the game is over when either player is wiped out.
a. What is the probability that Ben is ruined; that is, that Jerry will wipe him out?
b. What is the probability that Jerry is ruined?