Q. If var$(x) =$8.25, var$(y) =$33.96 and $cov(x,y) = 10.2$ then the correlation coefficient is
A) 0.89
B) -0.98
C) 0.61
D) -0.16
Explanation
(c)
$r_{xy} = \frac{cov(x,y)}{\sqrt{var(x)var(y)}}$
$= \frac{10.2}{\sqrt{(8.25)(33.96)}} = 0.61$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.