Two cricket teams of Lahore city play a tournament; it is decided that the team which win 4 games first, announced as the winner of the tournament. One teams is strong while other is week, suppose that stronger team wins each game with probability 0.6. If both the cricket teams played i = 4, 5, 6 and 7 matches evenly and each has probability 1/2 of winning each game then find the expected number of games played.