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Back to Calculate the expected value of a random variable — Problem 2 · Task Set 28

Exercises: Calculate the Expected Value of a Random Variable

Work through each section in order. Compute expected value with
E(X)=∑x⋅P(X=x)E(X) = \sum x \cdot P(X = x): multiply each value by its probability, then
add. Show each term as "value times its probability" before summing. For
payoff problems, write losses as negative values. Remember that E(X)E(X) is the
mean of the distribution and need NOT be a value the variable can actually take.

Grade 11·22 problems·~35 min·Common Core Math - HS Statistics and Probability·group·hss-md-a-2
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A

Warm-Up: Distributions and Weighted Means

These problems review probability distributions and the weighted-average idea you already know.

1.

For a probability distribution, the mean of the distribution, written μ\mu, is the same quantity as which of the following?