Question

Dr. Smith is concerned about absenteeism among his statistics students. The information below reports the number of days absent for a sample of 10 students during the last two-week exam period.

3 2 1 3 3 5 4 0 1 4

a- Determine the mean and the standard deviation of the sample.

b- What is the population mean? What is the best estimate of that value?

c- Develop a 95 percent confidence interval for the population mean.

d- Explain why the t distribution is used as a part of the confidence interval.

e- Is it reasonable to conclude that the typical student does not miss any days during an exam period?

Answer #1

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