In a study, nine tires of a particular brand were driven on a track under identical conditions. Each tire was driven a particular controlled distance (measured in thousands of miles), and afterward the tread depth was measured. Tread depth is measured in “mils.” Here, 1 mil is 0.001 inch. The least-squares regression line was computed, and added to a scatterplot of these data. On the plot, one data point is marked with an “X”.

Question

The equation of the least-squares regression line is:

Tread Depth = 360.64 – 11.39x (thousands of miles)

Also, r2 = 0.953.

The least-squares line would predict that the tread depth of a tire driven 16 thousand miles would be?

Answer 1

Substitute 16 for x and solve for tread depth in the equation.

Answer 2

Thank you! :)

Answer 3

178