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Calculate the Expectation and Variance

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

Value x of X P(X = x)
0 0.5
10 0.55
20 0.05
30 0.10
40 0.10
50 0.15

Find the expectation E(X) and the variance var(x) of X.

1. E(X) =
2. Var(X) =

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Solution Summary

In the following question, mean and variance are calculated for a probability distribution where the values and their associated probabilities are provided. This solution includes two brief calculations.

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