In each play of a game the probability of winning is 1/3. In 3 plays, what is the probability of exactly 1 wins?
Answer and explanation
Correct answer: B. 4/9
- Step 1: Use the binomial formula: P = nCk x p^k x (1 - p)^(n - k). Step 2. = 3 x (1/3)^1 x (2/3)^2 = 4/9. Answer: 4/9. Why not the others: 1/3: That is the probability of one particular sequence of the wins, with no losses considered. 5/9: That is the probability of not getting exactly this number, which is 1 minus the answer. 4/27: That omits the number of orders in which the wins can occur.
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