There is 1 way to win 6 games in a row wwwwww There are 2 ways to win 5 games in a row wwwwwl, lwwwww There are 5 ways to win 4 games in a row llwwww, wwwwll, lwwwwl, wlwwww, and wwwwlw. There are 2^n to arrange 6 wins and losses which adds up to 2^(6) = 64 So the Probability they win all four games in a stretch is 5 + 2 + 1 ways = 8 ways. So the probability = 8/64 = 1/8