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Chapter 3: Q 9. (page 171)

Does fast driving waste fuel? How does the fuel consumption of a car change as its speed increases? Here are data for a British Ford Escort. Speed is measured in kilometers per hour and fuel consumption is measured in liters of gasoline used per 100 kilometers traveled.

a. Make a scatterplot to display the relationship between speed and fuel consumption.

b. Describe the relationship between speed and fuel consumption.

Short Answer

Expert verified

Part (b) There is a decline in speed to 60km/hr and it has increased rapidly.

Part (a)

Step by step solution

01

Part (a) Step 1: Given information

The data set is:

02

Part (a) Step 2: Explanation

The scatter plot for the provided set can be constructed as:

03

Part (b) Step 1: Explanation

The scatter plot created in the previous section reveals that the variables fuel and speed have a non-linear relationship. The speed has dropped to 60 km/hr and is fast increasing.

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