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Mathematics

Expected Value in Probability

Quick fact

Expected value is like a 'weighted average'—it takes into account both the possible outcomes and their likelihoods to give a single numerical estimate of what might happen on average.

Why this is interesting

Imagine you're playing a game where you can win or lose money based on the roll of a die. How could you predict whether it's worth playing in the long run? The answer lies in expected value.