Calculate the coefficient of correlation between x and y.

By actual mean method :

$$\overline{X}=\ \frac{\sum{X}}{N}=\ \frac{523}{12}=43.86 , \overline{Y}=\ \frac{\sum{Y}}{N}=\ \frac{309}{12}=25.25$$ $$b_{xy}=\ \frac{\sum{xy}}{\sum{x^2}} = \frac{-319.25}{252.912}=\ -1.26$$ $$b_{xy}=\ \ \frac{\sum{xy}}{\sum{y^2}}=\ \frac{-319.25}{736.255}=\ -0.4336$$ $$r = \sqrt{b_{xy}*b_{yx}\ }=\ \sqrt{-0.4336*\ -1.26}=\ 0.739$$

Since $b_{xy}$ and $b_{yx}$ both are negative

Therefore , coefficient of correlation (r) is negative = -0.739