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The following is the p.d.f. of r.v. X : f(x) = x8, for 0 < x < 4 and = 0 otherwise (b) P ( 1 < x < 2 ) - Mathematics and Statistics

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Question

The following is the p.d.f. of r.v. X :

f(x) = `x/8`, for 0 < x < 4 and = 0 otherwise

P ( 1 < x < 2 )

Sum
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Solution

 P (1 < x < 2)

= ` int_(1)^2 f (x) dx`

= ` int_(1)^2 x/8 dx`

`1/8[x^2/2]_1^2`

=`1/8[4/2-1/2]`

=`3/16`

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Chapter 7: Probability Distributions - Exercise 7.2 [Page 239]

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