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प्रश्न
Find the expected number of boys in a family with 8 children, assuming the sex distribution to be equally probable.
उत्तर
Here, n =8
Let p be the probability of number of boys in the family.
\[p = \frac{1}{2}, q = \frac{1}{2}\]
\[\text{ Expected number of boys = mean } \]
\[ \Rightarrow np = 4\]
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