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A class has 12 boys and 4 girls. If thre...

A class has 12 boys and 4 girls. If three students are selected at random from the class,
what is the probability that all will be boys?

A

`1/55`

B

`1/4`

C

`1/3`

D

`11/28`

Text Solution

Verified by Experts

The correct Answer is:
D
There are 16 students altogether. The probability that the first person chosen
is a boy is `12/16`. Now there are only 15 students left, of which 11 are boys , so the
probability that the second student chosen is also a boys is `11/15`. By the same reasoning,
the probability that the third is a boy is `10/14`. Therefore, the probability that the first
and the second and the third students chosen are all boys is `12/16xx11/15xx10/14=11/28`.
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