12.1 Car mileage and weight The Car Weight and Mileage data file on the book’s website shows the weight (in pounds) and mileage (miles per gallon) of 25 different model autos.

a. Identify the natural response variable and explanatory variable.

b. The regression of mileage on weight has MINITAB regression output

State the prediction equation and report the y-intercept and slope.

c. Interpret the slope in terms of a 1,000-pound increase in the vehicle weight.

d. Does the y-intercept have any contextual meaning for these data? (Hint: The weight values range between 2,460 and 6,400 pounds.)

Transcribed Image Text:

Term Constant weight Coef 45.65 -0.005222 SE Coef T-Value P-Value 2.60 17.54 0.000 0.000627 -8.33 0.000