Chapter 14.2, Problem 11E

Sporty cars are designed to provide better handling, acceleration, and a more responsive driving experience than a typical sedan. But, even within this select group of cars, performance as well as price can vary. Consumer Reports provided road-test scores and prices for the following 12 sporty cars (Consumer Reports website. October 2008). Prices are in thousands of dollars and road-test scores arc based on a 0–100 rating scale, with higher values indicating better performance.

Car	Price ($1000s)	Road-Test Score
Chevrolet Cobalt SS	24.5	78
Dodge Caliber SRT4	24.9	56
Ford Mustang GT (V8)	29.0	73
Honda Civic Si	21.7	78
Mazda RX-8	31.3	86
Mini Cooper S	26.4	74
Mitsubishi Lancer Evolution GSR	38.1	83
Nissan Sentra SE-R Spec V	23.3	66
Suburu Impreza WRX	25.2	81
Suburu Impreza WRX Sti	37.6	89
Volkswagen GTI	24.0	83
Volkswagen R32	33.6	83

1. a. Develop a scatter diagram with price as the independent variable.
2. b. What does the scatter diagram developed in part (a) indicate about the relationship between the two variables?
3. c. Use the least squares method to develop the estimated regression equation.
4. d. Provide an interpretation for the slope of the estimated regression equation.
5. e. Another sporty car that Consumer Reports tested is the BMW 135i; the price for this car was $36,700. Predict the road-test score for the BMW 135i using the estimated regression equation developed in part (c).