Question

If the correlation coefficient between two random variables X and Y is 0.6, then the value of

correlation coefficient for r(-X,Y) is

(a) -0.6 (b) 0.6 (c) 1.2 (d) none​

Answer 1

Answer:

Correct option is

C81

r(X,Y)=

Var(X)⋅Var(Y)

cov(X,Y)

⇒

0.6=

Var(X)⋅25

27

⇒

Var(X)

=

0.6×5

27

∴

Var(X)=

81.