5. Problem 10-25
An appliance manufacturer wants to contract with a repair shop to handle authorized repairs in
Indianapolis. The company has set an acceptable range of repair time of 50 minutes to 90
minutes. Two firms have submitted bids for the work. In test trials, one firm had a mean repair
time of 74 minutes with a standard deviation of 4.0 minutes and the other firm had a mean repair
time of 72 minutes with a standard deviation of 5.1 minutes. (Do not round intermediate
calculations. Round your answers to 2 decimal places.)
Firm
Cpk
Which firm would you choose?
6. Problem 10-28
The following is a control chart for the average number of minor errors in 22 service reports.