# The Expectation and Variance of a Random Variable

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

Value x of X P(X=x)

-10 0.05

0 0.30

10 0.40

20 0.10

30 0.15

Find the expectation E(X) and variance VAR(X) of X.

E(x)=

Var(X)=

https://brainmass.com/statistics/variance/expectation-variance-random-variable-268000

#### Solution Summary

This solution examines the expectation and variance of a random variable.

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