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प्रश्न
Given X ~ B (n, p)
If n = 10 and p = 0.4, find E(X) and var (X).
उत्तर
Given, n = 10, p = 0.4
q = 1 – p = 1 – 0.4 = 0.6
Now, E(X) = np = 10 x 0.4 = 4
Var(X) = npq = 10 x 0.4 x 0.6 = 2.4
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