Question

E[X] = 2, E[X^2] = 8, E[Y] = 8, E[Y^2] = 100, and Var(X +Y) = 60. What is ρ(X, Y ), the correlation of X and Y

Answer #1

We are given that:

Now, the variance of X and that of Y is given by:

Now, consider the identity:

Thus, the correlation of X and Y is given by:

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