# Expectation and variance of a random variable

Let be a random variable with the following probability distribution:

Value Value

x of X P(X=x)

4 0.30

5 0.05

6 0.20

7 0.30

8 0.10

9 0.05

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

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Expectation and variance of a random variable

Let be a random ...

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The expert examines expectation and variances for sample solutions.

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