Suppose that X is a random variable with mean 20 and standard deviation 5 . Also...

Suppose that X is a random variable with mean 20 and standard deviation 5 . Also suppose that Y is a random variable with mean 45 and standard deviation 12 . Find the variance and standard deviation of the random variable Z for each of the following cases

(Give your answer to three decimal places.)

a) Z = 4 + 11X

b) Z = 11X − 4

c) Z = X + Y

d) Z = X − Y

e) Z = −2X − 4Y

Solutions

Expert Solution

orchestra answered 1 year ago

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