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प्रश्न
In a binomial distribution, if n = 20 and q = 0.75, then write its mean.
उत्तर
n= 20 , q =0.75
\[\Rightarrow p = 1 - q = 0 . 25\]
\[\text{ Mean = np } = 20(0 . 25) = 5\]
\[\text{ Thus, mean } = 5\]
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