Answer: -0.64
Step-by-step explanation:
We know that the coefficient of determination in a simple linear regression model is denoted by [tex]r^2[/tex], which gives the proportion of the variance in the dependent variable that is predictable from the independent variable.
Given, the coefficient of determination in a simple linear regression model is 64%.
i.e.
[tex]r^2= 0.64\\\\\Rightarrow\ r=\sqrt{0.64}=\pm 0.64[/tex]
As there is negative relation between the dependent and independent variables.
Then, the correlation coefficient = -0.64
