Q. The two lines of regression are given by $3x + 2y = 26\ and\ 6x + y = 31.$The coefficient of correlation between $x\$and$\ y\$is
A) $- 1/3$
B) $1/3$
C) $-$1/2
D) 1/2
Explanation
(c)
Given, $3x + 2y = 26$
$\Rightarrow y = - \frac{3}{2}x + 13$
And $6x + y = 31$
$\Rightarrow \ \ x = - \frac{1}{6}y + \frac{31}{6}$
$\therefore\ \ r = - \sqrt{\left( \frac{- 3}{2} \right)\left( \frac{- 1}{6} \right)}$
$\Rightarrow r = - \frac{1}{2}$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.