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Question
NARRBEGIN: SA_106_109The manager of a local fast-food restaurant is interested in improving service provided to customers who use the restaurant's drive-up window. As a first step in the process, the manager asks his assistant to record the time (in minutes) it takes to serve a large number of customers at the final window in the facility's drive-up system. The given frame in this case is 200 customer service times observed during the busiest hour of the day for this fast-food restaurant. The frame of 200 service times yielded a mean of 0.881. A simple random sample of 10 from this frame is presented below.
| Customer | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| Service time | 1.02 | 1.18 | 0.95 | 0.90 | 0.85 | 1.10 | 0.75 | 0.60 | 1.25 | 1.00 |
(A) Compute the point estimate of the population mean from the sample above. What is the sampling error in this case? Assume that the population consists of the given 200 customer service times.
(B) Compute the point estimate of the population standard deviation from the sample above.
(C) Should you use the finite population correction (fpc) factor to estimate the standard error of
? Explain. If your answer is yes, what is the value of the fpc?(D) Determine a good approximation to the standard error of the mean in this case.
Answer
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