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Twenty-five percent of a group of unrela...

Twenty-five percent of a group of unrelated students are only children. The students are asked one at a time whether they are only children. What is the probability that the 5th student asked is the first only child?

A

0.00098

B

0.08

C

0.24

D

0.25

Text Solution

Verified by Experts

The correct Answer is:
B
Whether or not students in the group have siblings are independent events. The probability that each of the first four is not an only child is `(0.75)^(4)`. The probability that the fifth student is an only is 0.25, so the probability of seeing the first four children with siblings and the fifth an only child is `(0.75)^(4)(0.25)~~0.08`.
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