Alenorm-- did you get my last question?? - Car Audio & Video

a). No. of ways in which 12 Last card is played in the last 50 games is 50C12. For the last game to be last card, 11 games of last card must be played in first 49 games and this can be done in 49C11 ways.

So, the probability in this case = 49C11/50C12 = 12/50 = 6/25..

b). No. of ways in which Sara can win 21 of last 50 games is 50C21. Probability of Sara winning the first game = 1C1 * 49C20. = 49C20.
So, probability that sara won't win the First game = 1 - (49C20).

Hope this one solved your problem. If you have additional doubts, please come back to us.


Regards
Sunny.


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