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Question
Given that X ~ B(n, p), if n = 10 and p = 0.4, find E(X) and Var(X)
Solution
X ~ B(n, p)
Here, n = 10, p = 0.4
∴ q = 1 – p = 1 – 0.4 = 0.6
E(X) = np = 10 × 0.4 = 4
Var(X) = npq = 10 × 0.4 × 0.6 = 2.4
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