Question

# Given two lines of regression $$x+3y=11$$ and $$2x+y=7$$. Find the coefficient of correlation between x and y.

A
r=0.408
B
r=0.408
C
r=0.108
D
r=0.108

Solution

## The correct option is A $$r=-0.408$$$$x+3y=11$$$$y=\cfrac{11}{3}-\cfrac{x}{3}$$So, $$b_{yx}=\cfrac{-1}{3}$$$$2x+y=7$$$$x=\cfrac{7}{2}-\cfrac{1}{2}y$$So, $$b_{yx}=\cfrac{-1}{2}$$ $$r=\sqrt{b_{xy}.b_{yx}}=\sqrt{\cfrac{-1}{2}\times \cfrac{-1}{3}}=\sqrt{\cfrac{1}{6}}=0.408$$Since $$b_{xy}$$ and $$b_{yx}$$ are negative.$$r=-0.408$$Maths

Suggest Corrections

0

Similar questions
View More

People also searched for
View More