Find the expected number of boys in a family with 8 children, assuming the sex distribution to be equally probable.

Let n and p be the parameters of the binomial distribution.


Let, p = probability of having a boy in the family


Given, p = q


Since, p + q = 1


p + p = 1


2p = 1




Given, n = 8


The expected number of boys = np



= 4


The expected number of boys = 4


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