Expected Value Calculator
Enter each outcome and its probability, as decimals or fractions. The calculator checks that the probabilities sum to 1, then works out E(X) and Var(X) in a table.
What you can do
- E(X), E(X²), Var(X) and the standard deviation
- A check that the probabilities add up to 1
- Probabilities typed as fractions, such as 1/6
- A working table of xP(x) and x²P(x)
- The distribution plotted, with the mean and spread marked