Question

What is the mean of this discrete random variable? (That is, what is E(X), the expected value of X?)

X: 8 9 12 13 16 23
P(X): 0.23 0.21 0.15 0.24 0.10 0.07

Answer 1

To find the mean, multiply each score X with its associated probability, and then add them together

\[\mu(x) = \sum_{i=1}^{n} x _{i} P(x _{i})\]