Q:

An engineer wants to determine how the weight of a​ car, x, affects gas​ mileage, y. The following data represent the weights of various cars and their miles per gallon. Car A B C D E Weight​ (pounds), x 2555 2900 3330 3725 4100 Miles per​ Gallon, y 21.8 20.5 19 14.2 11.6 ​(a) Find the​ least-squares regression line treating weight as the explanatory variable and miles per gallon as the response variable. Write the equation for the​ least-squares regression line.

Accepted Solution

A:
Answer:The ecuation of the line isy=-0.0068X+40Step-by-step explanation:Hello! To solve this question we must use the least-squares regression line equation, the equation is as followsY=mx+bThe values ​​of m and b are found using the formulas in the attached imageTo solve then we will use a table that to organize and extract all the values ​​of the summations.-Sum of X values-Sum of Y values- Sum of the product of X and Y-sum of x squared-------X------------Y ---------(X)(Y)----------x^2  1)---- 2555------21,8 -----55699-----6528025  2)----2900------20,5----59450------8410000  3)----3330------19------- 63270-------11088900  4)---3725------14,2------52895------13875625  5)----4100-------11,6-------47560------16810000  ------16610----- 87,1------278874-----56712550 SUMATORIESNow we use the ecuation in atached image remember that n= number of values =5[tex]m=\frac{5(278874)-(16610)(87.1)}{5(56712550)-(16610)^2}=-0.0068[/tex][tex]b=\frac{(87.1)(56712550)-(16610)(278874)}{5(56712550)-16610^2} =40[/tex]The ecuation of the line isy=-0.0068X+40