21. Processing Insurance Claims. An insurance company samples claim forms for errors created by its employees as well as the amount of time it takes to process a claim.

a. When the process is in control, the proportion of claims with an error is .033.

A p chart has LCL = 0 and UCL = .068. Plot the following seven sample results:

.035, .062, .055, .049, .058, .066, and .055. Comment on whether there might be concern about the quality of the process.

b. An x chart for the mean processing time has LCL = 22.2 and UCL = 24.5. The mean is m = 23.35 when the claim process is in control. Plot the following seven sample results: 22.4, 22.6, 22.65, 23.2, 23.4, 23.85, and 24.1. Comment on whether there might be concern about the quality of the process.