The following is the p.d.f. of r.v. X: f(x) = x8, for 0 < x < 4 and = 0 otherwise. Find P (x < 1·5) - Mathematics and Statistics

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Sum

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

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

Find P (x < 1·5)

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Solution

P (x < 1·5)

= ` int_(0)^1.5 f (x) dx`

= ` int_(0)^1.5 x/8 dx`

= `1/8[x^2/2]_0^1.5`

= `(1.5)^2/16 - 0`

=`((9/4))/16`

= `9/64`.

Concept: Probability Distribution of Discrete Random Variables
  Is there an error in this question or solution?
Chapter 7: Probability Distributions - Exercise 7.2 [Page 239]

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