Determine the mean and variance of the random variable in Exercise 3-18.

Answer

Step 1 of 1

(a)

We have given the probability mass function (PMF)

We are asked to find the mean and variance of the random variable.

We can form the probability mass function (PMF) table:

The mean or expected value of the discrete random variable denote a is

……….(1)

Using the PMF table, we can write the mean of a random variable,

Hence the mean of a random variable is

The variance of the discrete random variable denote a is

……….(2)

Hence the variance of a random variable is