Question

The covariance between x & y is 12, standard deviation of x is 3 & standard deviation of y is 5, then the correlation between X & Y is​

Answer 1

Answer:

given that,

r  

xy

​  

=0.48Var(x)=16cov(x,y)=36

r  

xy

​  

=  

Var(x)⋅Var(y)

​  

 

cov(x,y)

​  

 

⇒0.48=  

16×Var(y)

​  

 

36

​  

 

⇒2.304=  

16×Var(y)

36×36

​  

 

⇒Var(y)=  

2.304×16

36×36

​  

 

∴Var(y)=35.15

∴σ  

y

​  

=  

Var(y)

​  

=  

35.15

​  

=5.92