Question

1. The electric power consumed each month by a chemical plant is thought to be related to the average ambient temperature (x₁), the number of days in the month (x₂), the average product purity (x₃), and the tons of product produced (x₄). The past year’s historical data are available and are presented in the following table

x1	x2	x3	x4	y
25.00	24.00	91.00	100.00	240.00
31.00	21.00	90.00	95.00	236.00
45.00	24.00	88.00	110.00	270.00
60.00	25.00	87.00	88.00	274.00
65.00	25.00	91.00	94.00	301.00
72.00	26.00	94.00	99.00	316.00
80.00	25.00	87.00	97.00	300.00
84.00	25.00	86.00	96.00	296.00
75.00	24.00	88.00	110.00	267.00
60.00	25.00	91.00	105.00	276.00
50.00	25.00	90.00	100.00	288.00
38.00	23.00	89.00	98.00	261.00

a. Fit a multiple linear regression model to these data.

b. Predict power consumption for a month in which x₁ =75° F, x₂ = 24 days, x₃ = 90% and x₄ = 98 tons.

Answer 1