An engineer wants to determine how the weight of a car, x, affects gas mileages, y. The following data represent the weight of various cars and their miles per gallon.
Car A B C D E
Weight pounds, x 2660 2910 3290 3860 4015
Miles per Gallon, y 22.2 22.9 21.8 15.9 14.1
(a) Find the least-squares regression line treating weight as the explanatory variable and miles per gallon as the response variable. Write equation for the least-squares regression line.
Ŷ= (…..) x + (…….)(Round to four decimal places as needed).
(b) Interpret the slop and intercept, if appropriate.
(c) Predict the miles per gallon of car B and compute the residual. Is the miles per gallon of this car above average or below average for cars of this weights?
(d) Draw the least squares regression line on the scatter diagram of the data and label the residual.