Q.14 Given that, X sim B(n, p) , if n = 10,\ E(X) = 8 then find Var(X) .

Answer: Var(X) = 1.6 E(X) = np = 8 with n = 10 , so p = 0.8 and q = 1 - p = 0.2 . Var(X) = npq = 10 × 0.8 × 0.2 = 1.6 .

Given that, \(X \sim B(n, p)\), if \(n = 10,\ E(X) = 8\) then find \(\text{Var}(X)\).

Q.14 Given that, \(X \sim B(n, p)\), if \(n = 10,\ E(X) = 8\) then find \(\text{Var}(X)\).

Doubtly Asked 28 Oct 2026 Board exam · March 2026 hsc 12th Save WhatsApp Report

Best answer

Answer: \(\text{Var}(X) = 1.6\)

\(E(X) = np = 8\) with \(n = 10\), so \(p = 0.8\) and \(q = 1 - p = 0.2\).

\(\text{Var}(X) = npq = 10 \times 0.8 \times 0.2 = 1.6\).

Doubtly AI · 28 Oct 2026 AI-verified · Oct 2026 Report

Was this answer helpful?