Question

I need help with the last part of this problem - ​(d) Would it be reasonable to use the​ least-squares regression line to predict the miles per gallon of a hybrid gas and electric​ car? Why or why​ not? - Thank you so much!

An engineer wants to determine how the weight of a​ gas-powered car,​ x, affects gas​ mileage, y. The accompanying data represent the weights of various domestic cars and their miles per gallon in the city for the most recent model year.

Weight (pounds), x   Miles per Gallon, y
3729   16
3774   17
2694   24
3469   20
3355   20
2929   24
3731   18
2506   24
3559   19
3809   18
3253   17

​(a) Find the​ least-squares regression line treating weight as the explanatory variable and miles per gallon as the response variable.

ŷ =-0.0058x + 39.29

​(Round the x coefficient to five decimal places as needed. Round the constant to two decimal places as​ needed.)

(b) Interpret the slope and​ y-intercept, if appropriate. Choose the correct answer below and fill in any answer boxes in your choice. ​(Use the answer from part a to find this​ answer.)

A. A weightless car will get __?__miles per​ gallon, on average. It is not appropriate to interpret the slope.

B. For every pound added to the weight of the​ car, gas mileage in the city will decrease by 0.00585 mile(s) per​ gallon, on average. It is not appropriate to interpret the​ y-intercept.

C. For every pound added to the weight of the​ car, gas mileage in the city will decrease by __?__​mile(s) per​ gallon, on average. A weightless car will get __?__miles per​ gallon, on average. D. It is not appropriate to interpret the slope or the​ y-intercept. ​(c) A certain​ gas-powered car weighs 3600 pounds and gets 17 miles per gallon.

Is the miles per gallon of this car above average or below average for cars of this​ weight?

Below

Above

​(d) Would it be reasonable to use the​ least-squares regression line to predict the miles per gallon of a hybrid gas and electric​ car? Why or why​ not?

A. No, because the hybrid is a different type of car.

B. Yes, because the absolute value of the correlation coefficient is greater than the critical value for a sample size of n=11.

C. No, because the absolute value of the correlation coefficient is less than the critical value for a sample size of n=11.

D.Yes, because the hybrid is partially powered by gas.

Answer 1

Answer

Given data is only for gas powered car, so it is not good to use this data values and its least square line to make conclusion or decision about any other type of car

we know that gas powered car and hybrid car are different types of car, which we can never compare. So, it is better not use to gas powered car data to predict hybrid car

therefore, option A is correct answer because  hybrid is a different type of car.