Question

If the standard deviation of x is 15, the covariance of x and y is 94.5, the coefficient of correlation r = 0.90, then the variance of y is 7.0.

a. True
b. False

Answer 1

We have the formula

`Cov(X,Y)=\rho_(X,Y)√(Var(X)Var(Y))`

From the above formula,

`image`

That is variance of Y is 49 not 7.

Hence the statement is (b) False