Do heavier cars use more gasoline? To answer this question,a researcher randomly selected 15 cars.He collected their weight (in hundreds of pounds)and the mileage (MPG)for each car.From a scatter plot made with the data,a linear model seemed appropriate.The following output was obtained from SPSS: What is the equation of the least-squares regression line?
A)ŷ = -0.52 x + 0.164
B)ŷ = 40.44 - 0.52x
C)ŷ = 40.44 + 6.28x
D)y = 40.44 + 0.52x

Question

Do heavier cars use more gasoline? To answer this question,a researcher randomly selected 15 cars.He collected their weight (in hundreds of pounds)and the mileage (MPG)for each car.From a scatter plot made with the data,a linear model seemed appropriate.The following output was obtained from SPSS:   What is the equation of the least-squares regression line?
A)ŷ = -0.52 x + 0.164 
B)ŷ = 40.44 - 0.52x 
C)ŷ = 40.44 + 6.28x 
D)y = 40.44 + 0.52x

Quizplus · Accepted Answer

According to the output from SPSS, the equation of the least-squares regression line is ŷ = 40.44 - 0.52x. This means that the predicted mileage (ŷ) decreases by 0.52 for every increase of one unit in weight (x) in hundreds of pounds. Therefore, heavier cars use more gasoline as their mileage decreases.

Do Heavier Cars Use More Gasoline? to Answer This Question,a