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प्रश्न
In a family of 3 children, the probability of having at least one boy is
`(A)7/8`
`(B)1/8`
`(C)5/8`
`(D)3/4`
उत्तर
Correct answer: A
There are in all 23 = 8 combinations or outcomes for the gender of the 3 children
The eight combinations are as follows
BBB, BBG, BGB, BGG, GBB, GBG, GGB, GGG
Thus the probability of having at least one boy in a family is `7/8`
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