Question

Let X be a random variable with a mean of 9 and a variance of 16....

Let X be a random variable with a mean of 9 and a variance of 16. Let Y be a random variable with a mean of 10 and a variance of 25. Suppose the population correlation coefficient between random variables X and Y is -0.4.

a) Find the mean of the random variable W = 3X - 5Y.

b) Find the standard deviation of the random variable Z = X + Y

Homework Answers

Answer #1

We will use the formula above

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