Loading…
Loading…
SigmaCalc
What you'd average per play if you repeated this bet or decision many, many times.
For a bet with a -$5 or +$50 payoff, the expected value might be a number like $2.50 — an amount that never actually occurs on any single play. It only describes the long-run average across many repetitions.
Expected value underlies decision theory, gambling odds, insurance pricing, and investment analysis — anywhere you need to compare options with uncertain, probability-weighted outcomes on a single common scale.
Expected value
25
What you entered
Outcome 1 contribution
100 × 0.2= 20Outcome 2 contribution
50 × 0.3= 15Outcome 3 contribution
-20 × 0.5= -10Sum all contributions
20 + 15 + -10= 25Result
Expected value: 25
Weighting each outcome by its probability and summing gives an expected value of 25 — the long-run average result if this were repeated many times.