Suppose the Department of Energy would like to investigate the linear relationship between the cost of heating a home during the month of February in the Northeast and the home’s square footage. Data for a random sample of 10 homes are as follows:

Heating Cost ($)

Square Footage Heating Cost ($)

Square Footage 330 2,400 450 2,600 290 2,400 330 2,200 300 2,000 390 3,100 260 2,200 330 2,500 310 2,300 370 2,900

a. Construct a 90% confidence interval to estimate the average cost in February to heat a Northeast home that is 2,400 square feet.

b. Verify your results with PHStat.

AppendixLO1