What is Var (5X - 3Y)? we do not know X and Y are independent or not a. Var (X) + var(Y) b. 25Var (X) + 9Var (Y) + 30Cov (X,Y) c. 25Var (X) + 9Var (Y) - 30Cov (X,Y) d. 25Var (X) + 9Var (Y)
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The formula for the variance of a linear combination of random variables \(aX + bY\) is given by: \[ \text{Var}(aX + bY) = a^2 \text{Var}(X) + b^2 \text{Var}(Y) + 2ab \text{Cov}(X, Y) \] Show more…
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