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Question
The mean of a binomial distribution is 10 and its standard deviation is 2; write the value of q.
Solution
\[\text{ Mean of the binomial distribution, i . e . np } = 10\]
\[\text{ Variance } = \left( \text{ Standard deviation } \right)^2 ,\text{ i . e . npq } = 4\]
\[ \therefore q = \frac{\text{ Variance } }{\text{ Mean} } = 0 . 4 \]
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