If p.m.f. of r.v. X is given below. x 0 1 2 P(x) q2 2pq p2 then Var(x) = ______ - Mathematics and Statistics

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MCQ
Fill in the Blanks

If p.m.f. of r.v. X is given below.

x 0 1 2
P(x) q2 2pq p2

then Var(x) = ______

Options

  • p2

  • q2

  • pq

  • 2pq

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Solution

If p.m.f. of r.v. X is given below.

x 0 1 2
P(x) q2 2pq p2

then Var(x) = 2pq

Concept: Probability Distribution of Discrete Random Variables
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Chapter 2.8: Probability Distributions - Q.1

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