If the p.m.f. of a d.r.v. X is P(X = x) = {xn(n+1),for x=1, 2, 3, ....,n0,otherwise, then E(X) = ______ - Mathematics and Statistics

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MCQ
Fill in the Blanks

If the p.m.f. of a d.r.v. X is P(X = x) = `{{:(x/("n"("n" + 1))",", "for"  x = 1","  2","  3","  .... "," "n"),(0",", "otherwise"):}`, then E(X) = ______

Options

  • `"n" + 1/2`

  • `"n"/3 + 1/6`

  • `"n"/2 + 1/5`

  • `"n" + 1/3`

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Solution

`"n"/3 + 1/6`

Concept: Probability Distribution of Discrete Random Variables
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Chapter 2.7: Probability Distributions - MCQ

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