Given that X ~ B(n,p), if n = 10 and p = 0.4, find E(X) and Var(X) - Mathematics and Statistics

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Sum

Given that X ~ B(n, p), if n = 10 and p = 0.4, find E(X) and Var(X)

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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

Concept: Probability Distribution of Discrete Random Variables
  Is there an error in this question or solution?
Chapter 8: Probability Distributions - Exercise 8.3 [Page 151]

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