# 4M Cars in 1989 In order to have its cars meet the corporate average fuel economy (CAFE) standard,…

4M Cars in 1989

In order to have its cars meet the corporate average fuel economy (CAFE) standard, a manufacturer needs to improve the mileage of two of its cars. One design, a small sports car, weighs 2,500 pounds. The other model, a four-door family sedan, weighs 4,000 pounds. If it can improve the mileage of either design by two more miles per gallon, its cars will meet the federal standards.
Use the data for cars from the 1989 model year to answer these questions. Cars have changed since then, but many of the factors that influence mileage remain. The weight of the cars is measured in thousands of pounds, and the city mileage is expressed in miles per gallon.

Motivation

(a) Which of these two models should the manufacturer modify? In particular, if the manufacturer needs to reduce the weight of a car to improve its mileage, how can an equation that relates weight to mileage help?

Method

(b) Based on the analysis in this chapter for modern cars, what sort of relationship do you expect to find between weight and mileage (city driving) for cars from the 1989 model year—linear or curved?

(c) In order to choose the equation to describe the relationship between weight and mileage, will you be able to use summary measures like  , or will you have to rely on other methods to pick the equation?

Mechanics

(d) Create a scatterplot for mileage on weight. Describe the association between these variables.

(e) Fit an equation using least squares that captures the pattern seen in these data. Why have you chosen this equation?

(f) Do the residuals from your fitted equation show random variation? Do any outliers stand out?

(g) Compare the fit of this equation to that used in this chapter to describe the relationship between weight and mileage for more recent cars. Include in your comparison the slope and intercept of the fitted equation as well as the two summary measures,  and .

Message

(h) Summarize the equation developed in your modeling for the manufacturer’s management, using words instead of algebra.

(i) Provide a recommendation for management on the best approach to use to attain the needed improvement in fuel efficiency.

## Calculate the price of your order

550 words
We'll send you the first draft for approval by September 11, 2018 at 10:52 AM
Total price:
\$26
The price is based on these factors:
Number of pages
Urgency
Basic features
• Free title page and bibliography
• Unlimited revisions
• Plagiarism-free guarantee
• Money-back guarantee
On-demand options
• Writer’s samples
• Part-by-part delivery
• Overnight delivery
• Copies of used sources
Paper format
• 275 words per page
• 12 pt Arial/Times New Roman
• Double line spacing
• Any citation style (APA, MLA, Chicago/Turabian, Harvard)

# Our guarantees

Delivering a high-quality product at a reasonable price is not enough anymore.
That’s why we have developed 5 beneficial guarantees that will make your experience with our service enjoyable, easy, and safe.

### Money-back guarantee

You have to be 100% sure of the quality of your product to give a money-back guarantee. This describes us perfectly. Make sure that this guarantee is totally transparent.

### Zero-plagiarism guarantee

Each paper is composed from scratch, according to your instructions. It is then checked by our plagiarism-detection software. There is no gap where plagiarism could squeeze in.

### Free-revision policy

Thanks to our free revisions, there is no way for you to be unsatisfied. We will work on your paper until you are completely happy with the result.