7- Let X be a random variable with probability density functionx=1,2,5S(x)={8o.w.(a) Find the expected value and the variance of X.(b) Find the expected value and the variance of 2X+3.

Result used Y=ax+b E(Y)=aE(X)+b V(Y)=a2V(X) Var(X)=E(X2)-(E(X))2

Answered: 7- Let X be a random variable with…

A First Course in Probability (10th Edition)

10th Edition

ISBN:9780134753119

Author:Sheldon Ross

Publisher:Sheldon Ross

Chapter1: Combinatorial Analysis

Section: Chapter Questions

Problem 1.1P: a. How many different 7-place license plates are possible if the first 2 places are for letters and...

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7- Let X be a random variable with probability density function x=1,2,5 f(x)=8 O.w. (a) Find the expected value and the variance of X. (b) Find the expected value and the variance of 2X + 3.