There are 5 red marbles and 4 blue marbles in a bag. Bill and Ben are playing a game in which they take turns drawing a marble from the bag and then replacing it.
To win the game, n must draw a red marble and for Bill to win he must draw a blue marble. They continue taking turns until there is a winner. Ben goes first
Find the probability that Ben wins on his first draw.
Find the probability that Ben wins in three or less of his turns.
Find the probability that Ben wins the game.
Alice and Raoul take turns throwing darts at a dartboard. The winner is whoever hits the bullseye first. Alice has a chance of hitting the bullseye, while Raoul has a
40 chance of hitting the bullseye. Alice throws the first dart.
(a) Draw a tree diagram for the first four throws of the games (two throws for Alice and two for Raoul)
(b) What is the probability that Alice wins on her first or second throw?
(c) What is the probability that Alice will eventually win the game.