Question

Suppose the line of best fit is being found for some points that have an r-value of 0.769. If the standard deviation of the x-coordinates is 5.508, what is the slope of the line to three decimal places?

Answer 1

r value i.e Correlation between x value and y value = 0.769

$A_{x}$=Standard deviation of the x-coordinate = 5.508

 $A_{y}$=Standard deviation of the y-coordinate = ?=k

Slope of line is given by formula

If slope of line is m, then

m = $r\times \frac{ A_{x}}{A _{y}}$

m= $0.769 \times \frac{k}{5.508}$

Substitute the value of k, i.e Standard deviation of the y-coordinate and then you can get the slope of line to three decimal places.