Choose the correct option from the given alternative: If p.m.f. of a d.r.v. X is P (X = x) = xn(n+1), for x = 1, 2, 3, . . ., n and = 0, otherwise then E (X ) = - Mathematics and Statistics

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Choose the correct option from the given alternative:

If p.m.f. of a d.r.v. X is P (X = x) = `x^2 /(n (n + 1))`, for x = 1, 2, 3, . . ., n and = 0, otherwise then E (X ) =

Options

  • `n/ 1 + 1/ 2`

  • `n /3 + 1 /6`

  • `n/ 2 + 1 /5`

  • `n /1 + 1/ 3`

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Solution

If p.m.f. of a d.r.v. X is P (X = x) = `x^2 /(n (n + 1))`, for x = 1, 2, 3, . . ., n and = 0, otherwise then E (X ) = `n /3 + 1 /6`

Concept: Probability Distribution of Discrete Random Variables
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Chapter 7: Probability Distributions - Miscellaneous Exercise 1 [Page 242]

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Balbharati Mathematics and Statistics 2 (Arts and Science) 12th Standard HSC Maharashtra State Board
Chapter 7 Probability Distributions
Miscellaneous Exercise 1 | Q 6 | Page 242

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