Given that \(X\sim B(n,p)\). If \(n=10\) and \(p=0.4\) then \(E(X)\) and \(Var(X)\) respectively are ____.

Q.1 (vii) Given that \(X\sim B(n,p)\). If \(n=10\) and \(p=0.4\) then \(E(X)\) and \(Var(X)\) respectively are ____.

A. 4, 0.24

B. 0.4, 0.24

C. 4, 2.4

D. 3, 0.24

Doubtly Asked 29 Oct 2026 Board exam · July 2024 hsc 12th Save WhatsApp Report

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Answer: C. 4, 2.4

Answer: (c) 4, 2.4

\(E(X)=np=10\times0.4=4\); \(q=1-p=0.6\), so \(Var(X)=npq=10\times0.4\times0.6=2.4\).

Doubtly AI · 29 Oct 2026 AI-generated · not yet verified Report

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