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The student council consists of 10 juniors and 12 seniors. If two members are voted to be officers, what is the probability they are both seniors? Round the answer to two decimal places.

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To find the probability of two events without replacement, we can use the general multiplication rule, which states that:

P(A and B) = P(A) * P(B|A)

where P(A and B) is the probability of both events occurring, P(A) is the probability of the first event occurring, and P(B|A) is the probability of the second event occurring given that the first event has occurred.

In this case, we want to find the probability that both members are seniors. Let A be the event that the first member is a senior, and B be the event that the second member is a senior. Then:

P(A) = 12/22

since there are 12 seniors out of 22 members.

P(B|A) = 11/21

since there are 11 seniors left out of 21 members after choosing one senior.

P(A and B) = P(A) * P(B|A)

= (12/22) * (11/21)

= 132/462

= 0.2857

Rounding to two decimal places, the probability is **0.29**.

User Tony Gil
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