Because of staffing decisions, managers of the Gibson-Marimont Hotel are interested in the variability in the number of rooms occupied per day during a particular season of the year. A sample of 20 days of operation shows a sample mean of 290 rooms occupied per day and a sample standard deviation of 30 rooms.

a. What is the point estimate of the population variance (to nearest whole number)?

b. Provide a 90% confidence interval estimate of the population variance (to nearest whole number). Use Table 11.1.

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c. Provide a confidence 90% interval estimate of the population standard deviation (to 1 decimal). Use Table 11.1.

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