Question

Let X be a random variable with the following probability distribution: Value x of X P(X=x)...

Let X be a random variable with the following probability distribution:

Value

x

of

X

P(X=x)

20 0.15
30 0.15
40 0.30
50 0.40

Find the expectation

E(X) and variance Var (X) of X.

Homework Answers

Answer #1

Given Probability distribution of X is:

X P(X=x)

20 0.15

30 0.15

40 0.30

50 0.40

The expectation of X is given by:

The variance of X is given b y:

i.e

The variance of X is  

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