Assume that X, Y, and Z are independent random variables and that each of the random...

Assume that X, Y, and Z are independent random variables and that each of the random variables have a mean of 1. Further, assume σ_X = 1, σ_Y = 2, and σ_Z = 3. Find the mean and standard deviation of the following random variables:

a. U = X + Y + Z

b. R = (X + Y + Z)/3

c. T = 2·X + 5·Y

d. What is the correlation between X and Y?

e. What is the covariance between Q and G, where Q = 2·Y + 3 and G = 4·Z - 6?

Expert Solution

orchestra answered 2 years ago

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