Question

1. A sample of the salaries of 10 employees of a small company are listed below, with unit of “thousand dollars”.

26

29

31

36

37

41

41

45

56

63

1. Find the mean and standard deviation of the sample data by hand.

26	40.5	-14.5	210.25
29	40.5	-11.5	132.25
31	40.5	-9.5	90.25
36	40.5	-4.5	20.25
37	40.5	-3.5	12.25
41	40.5	0.5	0.25
41	40.5	0.5	0.25
45	40.5	4.5	20.25
56	40.5	15.5	240.25
63	40.5	22.5	506.25
405			1232.5

1. Verify the calculations using Excel. What are the sample mean and sample standard deviation from Excel (use AVERAGE and STDEV functions)?
2. Find the 5-number summary of the data, and make a boxplot by hand.
3. Verify the 5-number summary found in (3) in Excel. What are the 5-number summary provided by Excel (use QUARTILE function)?

Answer 1