Tessler Electric utility requires service operators to answer the telephone calls from customers in an average time of 0.1 minute or less. A sample of 30 actual operator times are drawn, and the results are given in the following table. In addition, operators are expected to determine customer needs and either respond to them or refer the customer to the proper department within 0.5 minute. Another sample of 30 times was taken for this job component and is also given in the table. If these variables can be considered to be independent, is the average time to perform each component statistically different form the standard.
Component Mean Time Standard Deviation
Answer 0.1023 0.0183
Service 0.5290 0.0902
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