14.5 THE SERVICE TIME CASE Accu-Copiers, Inc., sells and services the Accu-500 copying machine. As part of its standard service contract, the company agrees to perform routine service on this copier....

14.5 THE SERVICE TIME CASE

Accu-Copiers, Inc., sells and services the Accu-500 copying machine. As part of its standard service contract, the company agrees to perform routine service on this copier. To obtain information about the time it takes to perform routine service, Accu-Copiers has collected data for 11 service calls. The data and Excel output from fitting a least squares regression line to the uploaded data:

a. Find the least-squares point estimates b0 and b1 on the computer output and report their values. Interpret b0 and b1. Does the interpretation of b0 make practical sense?

b. Use the least squares line to compute a point estimate of the mean time to service four copiers and a point prediction of the time to service four copiers on a single call.