Cellulon, a manufacturer of home insulation, wants to develop guidelines for builders and consumers on how the thickness of the insulation in the attic of a home and the outdoor temperature affect natural gas consumption. In the laboratory, it varied the insulation thickness and temperature. A few of the findings are: Monthly Natural Gas Consumption (cubic feet), Thickness of Insulation (inches), Outdoor Temperature (ºF),
y x1 x2
30.3 6.0 32.0
25.2 12 40
30.5 8 49
On the basis of the sample results, the regression equation is:
yˆ y⁢^⁢  = 57.25 − 1.07x1 − 0.64x2