Q. If $\ \overline{x} = \overline{y} = 0,\ \sum_{}^{}{x_{i}y_{i}} = 12,\ \sigma_{X} = 2,\ \sigma_{Y} = 3$ and $n = 10$, then the coefficient of correlation is
A) 0.1
B) 0.3
C) 0.2
D) 0.-1
Explanation
(c)
$r = \frac{\frac{1}{n}\Sigma xy - \overline{x}\overline{y}}{\sigma_{x} \times \sigma_{y}} = \frac{\frac{1}{10} \times 12 - 0}{2 \times 3} = 0.2$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.