Question

Ari independent mall delivery service wants to study factors that affect the daily gas usage of its delivery trucks. Using data collected fram different trichs on various days, a compamy analyst uses software to fit a regression model of the following form. y=19.8+9.9x 1 −2.6x 2+5x 3 +0.06x4 In this model are the folsowing variables. y= volume of gasoline used (in gallons) x

1 = weight of truck (in tons) x 2= tire pressure (in psi, pounds per square inch) x 3 = weight of initial package load (in hundreds of pounds) N 4 - total distance driven while delivering packages (in males) Answer the questions below for the interpretation of the coetficient of x in this model. (a) ltolding the other variables fixed, what is the overage change in dazly fuet used tor each addiogal pound of air pressure (ber square inch) used in a truck's ties?

Answer 1

Holding other variables constant, each additional psi of tire pressure is associated with a decrease of 2.6 gallons in daily fuel usage.

Step-by-step explanation:

The question is asking about the interpretation of the regression coefficient for x2, which represents the tire pressure, in a regression equation predicting daily fuel usage. From the given regression equation y = 19.8 + 9.9x1 - 2.6x2 + 5x3 + 0.06x4, we can see that the coefficient for x2 is -2.6. This implies that holding other variables fixed, for each additional pound of air pressure per square inch in the truck's tires, the average change in daily fuel used is a decrease of 2.6 gallons.