You're playing a game in which the probability of winning each round is .20. On average, how many rounds do you have to play to first win?

Question

A. 20

B. 5

C. 15

D. .5

E. 10

Answer 1

The expected number of rounds to win is equal to 1/probability of winning, which in this case is 1/.20 = 5 rounds.

Therefore, the answer is B. 5