Suppose that X and Y are random variables such that var(X) = 9, var(Y) = 4, and ?(X, Y) = ?1/6. Determine (a) var(X + Y) (b) var(X ? 3Y + 4)
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We are given var(X) = 9, var(Y) = 4, and the correlation coefficient Ļ(X, Y) = -1/6. We can find the covariance using the formula: cov(X, Y) = Ļ(X, Y) * sqrt(var(X) * var(Y)) cov(X, Y) = (-1/6) * sqrt(9 * 4) = (-1/6) * 6 = -1 Now we can find var(X + Y): var(X Show moreā¦
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