GATE 2025 ST – Question 29

Standard Univariate Distributions · Discrete Distributions · 1 mark · Numerical answer

For X~Binomial(2,1/3), find 18E(X²) (integer).

Show answer and explanation

Correct answer: 16 to 16

Explanation

E X=2/3 and Var X=2(1/3)(2/3)=4/9. Thus E X²=4/9+(2/3)²=8/9, and 18×8/9=**16**.

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