हिंदी

The p.m.f. of a r.v. X is given by P (X = x) =(5Cx)25 , for x = 0, 1, 2, 3, 4, 5 and = 0, otherwise. Then show that P (X ≤ 2) = P (X ≥ 3). - Mathematics and Statistics

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प्रश्न

The p.m.f. of a r.v. X is given by P (X = x) =`("" ^5 C_x ) /2^5` , for x = 0, 1, 2, 3, 4, 5 and = 0, otherwise.

Then show that P (X ≤ 2) = P (X ≥ 3).

योग

उत्तर

P (X ≤ 2) = P(X = 0 ) + P(X = 1)+P(X = 2)

= `(""^5C_0)/2^5 + (""^5C_1)/2^5 + (""^5C_2)/2^5`

= `(""^5C_5)/2^5 + (""^5C_4)/2^5 + (""^5C_3)/2^5` ........[`""^nC_r = ""^nC_n-r`]

= P (X = 5) + P (X = 4) + P (X = 3)

= P (X ≥ 3 )

∴ P (X ≤ 2) = P (X ≥ 3).

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Types of Random Variables
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अध्याय 7: Probability Distributions - Miscellaneous Exercise 2 [पृष्ठ २४२]

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बालभारती Mathematics and Statistics 2 (Arts and Science) [English] 12 Standard HSC Maharashtra State Board
अध्याय 7 Probability Distributions
Miscellaneous Exercise 2 | Q 4 | पृष्ठ २४२

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