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In: Statistics and Probability

Consider independent random variables X1, X2, and X3 such that X1 is a random variable having...

Consider independent random variables X1, X2, and X3 such that X1 is a random variable having mean 1 and variance 1, X2 is a random variable having mean 2 and variance 4, and X3 is a random variable having mean 3 and variance 9.

(a) Give the value of the variance of

X1 + (1/2)X2 + (1/3)X3

(b) Give the value of the correlation of Y = X1- X2 and Z = X2 + X3.

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