1. A random sample of 37 employees in Sweden worked an average number of 231 days...
1. A random sample of 37 employees in Sweden worked an average number of 231 days per year. The sample standard deviation is 26 days.
a) Develop a 95% confidence interval for the average number of work-days per year for all Swedish employees. (6 marks)
b) Verbally interpret the meaning of the confidence interval that you found for part a)
c) If the desired margin of error for the above confidence interval is 4 days, what size sample is necessary? (Use the sample standard deviation given above as the planning value for the population standard deviation)
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