Question

For the following data of bivariate

$n = 25$ $\Sigma x = 125$ $\Sigma y = 100$

$\Sigma x ^ { 2 } = 650$ $\Sigma y ^ { 2 } = 436$ $\Sigma x y = 520$

The coefficient of correlation is

• A. 1/2
• B. 2/5
• C. 3/5
• D. 2/3

Answer 1

Answer: (D)

2/3

Answer 2

Proceed with the help of following formula

$r = \frac { \Sigma x y - \frac { \Sigma x \cdot \Sigma y } { n } } { \sqrt { \left\{ \Sigma x ^ { 2 } - \frac { ( \Sigma x ) ^ { 2 } } { n } \right\} \left\{ \Sigma y ^ { 2 } - \frac { ( \Sigma y ) ^ { 2 } } { n } \right\} } }$ =$\frac { 2 } { 3 }$.