Chapter 10, Problem 7E

(a)

To determine

To Explain: the association between these variables given in the scatter plot.

Explanation of Solution

Given:

  

By seeing the graph, it observed that the scatter plot, vertical axis displays the fuel efficiency and the horizontal axis displays the weight. As the weight is increasing the efficiency of the fuel is decreases. There is strong negative association between these two variables and it is fairly linear.

(b)

To determine

To find: the regression analysis for the linear model.

Explanation of Solution

Given:

  

By seeing the given output the slope of the line is -7.65184. It tells that gas mileage decreases an average 7.652 mpg for the each thousand pound of weight.

(c)

To determine

To find: that this linear model is appropriate or not.

Explanation of Solution

Given:

  

By seeing the plot, it noticed that the pattern is curved. The linear model is appropriate only if the residual figure does not display any pattern. So, the linear model is not appropriate. Therefore the linear model is not appropriate, although residual figure display a curved pattern.