Question

In: Math

Suppose X is a discrete random variable with mean μ and variance σ^2. Let Y =...

Suppose X is a discrete random variable with mean μ and variance σ^2. Let

Y = X + 1.
(a) Derive E(Y ).

(b) Derive V ar(Y ).

Solutions

Expert Solution

(a)

Given:

E(X) =

Var(X) =

Y = X + 1                         

To find E(X + 1):

Let p(X) be the Probability Mass Function of X.

Thus,

                     

                        

Thus, the answer is:

(b)

By Theorem:

Substituting

, we get:

                 

                                

                                 

                                    

                                   

Thus, the answer is:


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