Probability

Sum of Independent Random Variables

Compute E(X+Y) and Var(X+Y) for independent X and Y. Also computes E(X−Y) and Var(X−Y). Includes a visual showing how variances add when combining distributions.

Live Calculator · Step-by-Step · Probability
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Step-by-Step Work

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Distributions of X, Y, and X+Y (variances add)
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