Alice, Benjamin, and Carol each try independently to win a carnival game. If their individual probabilities for success are 1/5, 3/8, and 2/7, respectively, what is the probability that exactly two of the three players will win but one will lose?A. 3/140B. 1/28C. 3/56D. 3/35E. 7/40

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Answer:

The correct option is E.

Step-by-step explanation:

It is given that Alice, Benjamin, and Carol each try independently to win a carnival game.

Let A, B and C represent the following events.

A = Alice win

B = Benjamin win

C = Carol win

[tex]P(A)=\frac{1}{5}[/tex] and [tex]P(A')=1-P(A)=1-\frac{1}{5}=\frac{4}{5}[/tex]

[tex]P(B)=\frac{3}{8}[/tex] and [tex]P(B')=\frac{5}{8}[/tex]

[tex]P(C)=\frac{2}{7}[/tex] and [tex]P(C')=\frac{5}{7}[/tex]

We need to find the probability that exactly two of the three players will win but one will lose.

[tex]Probability=P(A\cap B\cap C')+P(A\cap B'\cap C)+P(A'\cap B\cap C)[/tex]

[tex]Probability=P(A)P(B)P(C')+P(A)P(B')P(C)+P(A')P(B)P(C)[/tex]

[tex]Probability=\frac{1}{5}\cdot\frac{3}{8}\cdot\frac{5}{7}+\frac{1}{5}\cdot\frac{5}{8}\cdot\frac{2}{7}+\frac{4}{5}\cdot\frac{3}{8}\cdot\frac{2}{7}[/tex]

[tex]Probability=\frac{3}{56}+\frac{1}{28}+\frac{3}{35}[/tex]

[tex]Probability=\frac{7}{40}[/tex]

The probability that exactly two of the three players will win but one will lose is [tex]\frac{7}{40}[/tex].

Therefore the correct option is E.