Question

B.Find the correlation coefficient for the following relationship. What does this tell us?

Answer 1

Step 1

Use a graphing calculator to graph the values in the table and the get the eqaution of the line of best fit and the regression

Step 2

Write the equation of the line

`\begin{gathered} \text{The equation of a line is given as} \\ y=\text{ ax+b} \\ a=\text{ -3.8} \\ b=\text{ 94.4} \\ \text{Hence } \\ y=-3.8x+94.4 \end{gathered}`

Step 3

Write the correlation coefficient , r

`r\text{ = }-0.9444`

Since r is closer to -1 than 1 then there is a negative relationship between the two variables.