# Expected value

Compute the expected value given a set of outcomes, probabilities, and payoffs.

### Problem

X is a discrete random variable. The table below defines a probability distribution for X.
What is the expected value of X?
xP, left parenthesis, X, equals, x, right parenthesis
minus, 70, point, 2
minus, 30, point, 1
30, point, 4
70, point, 3