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Expected value E(X) of discrete random variable:
AVariance
BΣ x_i P(x_i)
CBoth A and B are equivalent
DMean
Answer & Solution
Correct answer: C. Both A and B are equivalent
E(X) = Σ x_i P(x_i) = mean of distribution. Linearity: E(aX + b) = aE(X) + b. For continuous: ∫ x f(x) dx.
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