Chapter 8, Problem 2E

To determine

To find out what does this model suggest your gas mileage would be, if the car you are thinking of buying has a $200$ horsepower engine.

Answer to Problem 2E

  $30.07$ mpg.

Explanation of Solution

It is given in the question that, we examined in previous exercise about the relationship between the fuel economy in mpg and horsepower for models of cars. Thus, the analysis produced the regression model for the same:

  $\text{<mover accent="true"><mo>m</mo><mo>^</mo></mover> pg}=46.87-0.084\text{HP}$

Thus, if the car we are thinking of buying has a $200$ horsepower engine then the fuel economy in mpg will be calculated as:

  $\begin{array}{l}\text{<mover accent="true"><mo>m</mo><mo>^</mo></mover> pg}=46.87-0.084\text{Fiber}\\ =46.87-0.084\times 200\\ =30.07\end{array}$

Thus, $30.07$ mpg fuel economy is needed if the car we are thinking of buying has a $200$ horsepower engine.