✓ Effortless Math · Free Tool

Expected Value Calculator

Compute E(X) = Σ x·P(x) from a probability distribution — plus the variance and standard deviation — with a table and step-by-step working.

E(X) = Σ x · P(x)
values (x) probabilities P(x)

Enter the outcomes and their probabilities (comma-separated, same count). Fractions like 1/6 are allowed; probabilities should sum to 1.

Results

Expected value E(X)
E(X) = Σ x·P(x)
Variance
Std. deviation
Sum of probabilities

Distribution

Step-by-step