Concept explainers
Applying What You’ve Learned
In Exercises 17-26, it is useful to think of slope as representing the average rate of change of one variable corresponding to a change in the other variable. To keep the numbers you work with small, represent the first year for which you have data as year 0. For example, in Exercise 17, the year 2009 is year 0. In Exercise 24, the year 2010 is year 0.
Miles driven by millennials. In 2009, the number of miles driven per year by persons aged 16-34 was 7,900. Assume that the number of miles driven was decreasing by 300 miles per year.
a. Model this information with a linear equation.
b. Use this model to predict how many miles persons aged 16-34 will drive per year in 2019.
c. Explain why this model would not be expected to hold in 2030.
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Mathematics All Around (6th Edition)
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