Number of Hours Worked An economic researcher is collecting data about grocery store employees in a county. The data listed below represents a random sample of number of hours worked by 40 employees for several grocery stores in the county. Assume that the population standard deviation is 7.9 hours. An economics researcher wants to estimate the mean number of hours worked by all grocery store employees in the county. How many employees must be included in the sample to be 95% confident that the sample mean is within 1.5 hours of the population mean? 30, 26, 33, 26, 26, 33, 31, 31, 21, 37, 27, 20, 34, 35, 30, 24, 38, 34, 39, 31, 22, 30, 23, 23, 31, 44, 31, 33, 33, 26, 27, 28, 25, 35, 23, ,32, 29, 31, 25, 27

A company conducted a survey to determine the average age of its employees. The ages of 10 randomly selected employees are as follows: 25, 28, 30, 35, 40, 42, 45, 48, 50, and 55. Calculate the sample mean, sample variance, and standard deviation of the ages.

The table below summarizes the number of hours a sample of college students spent watching television in the past week. Hours Frequency 10 - 12 4 13 - 15 12 16 - 18 20 19 - 21 14 Find the standard deviation.

Two stores sell watermelons. At the first store the melons weigh an average of 22 pounds, with a standard deviation of 2.5 pounds. At the second store the melons are smaller. with a mean of 18 pounds and a standard deviation of 2 pounds. You take and SRS of 40 melons from the first store and SRS of 34 from the second store Find the mean of each sampling distribution

Calculate the mean, median and sample standard deviation for the following data.      1, 5, 2, 6, 8

TLe Citu University of 3. Find the standard deviation for the following sample data: Freq. 6. 7 8. 8. 1 6. 10 4 3.

z Scores LeBron James, one of the most successful basketball players of all time, has a height of 6 feet 8 inches, or 203 cm. Based on statistics from Data Set 1 “Body Data” in Appendix B, his height converts to the z score of 4.07. How many standard deviations is his height above the mean?

Dan is doing research on organic farming for an agricultural foundation. He has collected data on the number of oranges harvested from individual trees in two different orchards. In each orchard, the number of oranges harvested from each of 57 trees was recorded. The histograms below show the distributions of the two data sets. The means and standard deviations for the data sets are also given. Orchard 1 Orchard 2 25 25 20- 20- 15+ 15- 10+ 10+ 5+ 5+ 199.5 219.5 239.5 259.5 279.5 299.5 319.5 339.5 359.5 199.5 219.5 239.5 259.5 279.5 299.5 319.5 339.5 359.5 Orchard 1 mean: 275.1 oranges Orchard 2 mean: 274.9 oranges Orchard 1 standard deviation: 23.2 oranges Orchard 2 standard deviation: 47.9 oranges Dan wants to use the Empirical Rule to make some approximations about both data sets. Unfortunately, it is appropriate to use the Empirical Rule on only one of them! Answer the parts below to help Dan with his approximations. (a) Identify the data set for which it is appropriate to use the…