Officer Salaries. The following table gives the monthly salaries

(in $1000s) of the six officers of a company.

Officer AB C D E F Salary 8 12 16 20 24 28

a. Calculate the population mean monthly salary, μ.

There are 15 possible samples of size 4 from the population of six officers. They are listed in the first column of the following table.

Sample Salaries x¯

A, B, C, D 8, 12, 16, 20 14 A, B, C, E 8, 12, 16, 24 15 A, B, C, F 8, 12, 16, 28 16 A, B, D, E 8, 12, 20, 24 16 A, B, D, F 8, 12, 20, 28 17 A, B, E, F 8, 12, 24, 28 18 A, C, D, E A, C, D, F A, C, E, F A, D, E, F B, C, D, E B, C, D, F B, C, E, F B, D, E, F C, D, E, F

b. Complete the second and third columns of the table.

c. Complete the dotplot for the sampling distribution of the sample mean for samples of size 4. Locate the population mean on the graph.

14 15 16 17 18 19 20 21 22 x

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d. Obtain the probability that the mean salary of a random sample of four officers will be within 1 (i.e., $1000) of the population mean.