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Three friends (A, B, and C) will participate in a round-robin tournament in whic

ID: 3058857 • Letter: T

Question

Three friends (A, B, and C) will participate in a round-robin tournament in which each one plays both of the others. Suppose that

P(A beats B) = 0.7
P(A beats C) = 0.2
P(B beats C) = 0.9

and that the outcomes of the three matches are independent of one another.

(a) What is the probability that A wins both her matches and that B beats C?


(b) What is the probability that A wins both her matches?


(c) What is the probability that A loses both her matches?


(d) What is the probability that each person wins one match? (Hint: There are two different ways for this to happen.)

Explanation / Answer

Three friends (A, B, and C) will participate in a round-robin tournament in which each one plays both of the others. Suppose that

P(A beats B) = 0.7
P(A beats C) = 0.2
P(B beats C) = 0.9

and that the outcomes of the three matches are independent of one another.

(a) What is the probability that A wins both her matches and that B beats C?


(b) What is the probability that A wins both her matches?


(c) What is the probability that A loses both her matches?


(d) What is the probability that each person wins one match? (Hint: There are two different ways for this to happen.)