In the major league baseball world series, two teams A and B play a sequence of games against each other, and the first team that wins a total of four games wins the series. Suppose the outcomes of all games in the series are independent and that the teams A and B are close to even so that probability that A wins any particular game is 0.49 ( and so B wins any one game with probability 0.51). What is the expected number of games in the series?