# Question

Desert Samaritan Hospital in Mesa, Arizona, keeps records of emergency room traffic. Those records reveal that the times between arriving patients have a special type of reverse-J-shaped distribution called an exponential distribution. They also indicate that the mean time between arriving patients is 8.7 minutes, as is the standard deviation. Suppose that you observe a sample of 10 interarrival times.

a. Theoretically, what are the mean and standard deviation of all possible sample means?

b. Use the technology of your choice to simulate 1000 samples of 10 interarrival times each.

c. Determine the mean of each of the 1000 samples that you obtained in part (b).

d. Roughly what would you expect the mean and standard deviation of the 1000 sample means you obtained in part (c) to be? Explain your answers.

e. Determine the mean and standard deviation of the 1000 sample means you obtained in part (c).

f. Compare your answers in parts (d) and (e). Why are they different?

a. Theoretically, what are the mean and standard deviation of all possible sample means?

b. Use the technology of your choice to simulate 1000 samples of 10 interarrival times each.

c. Determine the mean of each of the 1000 samples that you obtained in part (b).

d. Roughly what would you expect the mean and standard deviation of the 1000 sample means you obtained in part (c) to be? Explain your answers.

e. Determine the mean and standard deviation of the 1000 sample means you obtained in part (c).

f. Compare your answers in parts (d) and (e). Why are they different?

## Answer to relevant Questions

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