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4. a) Response times were recorded for 40 randomly selected customers of phone company A answering...

4. a) Response times were recorded for 40 randomly selected customers of phone company A answering a phone call. Those times had a mean of 23.95 seconds and a standard deviation of 2.55 seconds. Construct a 99% C.I estimate of the population mean.

b) Response times were recorded for 35 randomly selected customers of phone company B answering a phone call. Those times had a mean of 18.95 seconds and a standard deviation of 1.30 seconds. Construct a 99% C.I estimate of the population mean.

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c) Use parts a) and b) to determine if Phone Company or Phone A, Company B is more efficient. Explain.

Math   Statistics-And-Probability   
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