5. Using Table 1, Find the mean, median, and mode of the data, if possible. If any of these measures cannot be found, explain why.

Table 1 / Cholesterol levels
201	251	237	212	260	244	218	215	251	256

6. Using Table 2, Find the mean, median, and mode of the data, if possible. If any of these measures cannot be found, explain why.

Table 2 / Number of aircraft
99	114	240	302	226	157	108	305
132	176	115	141	274	170	219

7. Using Table 3, Find the mean, median, and mode of the data, if possible. If any of these measures cannot be found, explain why.

Table 3 / Why students were not successful	Frequency
Incomplete assignments:	27
Poor exam performance:	22
Study time:	37
Schedule conflict with work:	23
Overloaded schedules:	12
Cost of texts:	24
Other:	5

8. Find the weighted mean of the data For the month of July, a checking account has a balance of $589.42 for 6 days, $839.62 for 12 days, $763.35 for 10 days, and $284.37 for 3 days. What is the account's mean daily balance for July? (Do not round until the last step; Round results to the nearest penny).

Section 2.4

Problems 9-12. Use the data set representing a sample in Table 4 to answer the questions (Note: Review the 1-Var Stats function on the TI83/84 calculator).

Table 4 / Sample Data
173	144	140	140	178
179	189	160	146	165
195	179	170	175	192
177	184	170	158	152

9. What is the range?

10. What is the mean?

11. What is the variance?

12. What is the standard deviation?

Problems 13-15. Use Tables 5a and 5a to answer the questions.

table 5a. /Data Set A:	1	2	3	4	5	95	96	97	98	99

Table 5b. / Data Set B:	1	46	47	48	49	51	52	53	54	99

13. Select the letter of the appropriate data set. Without calculating the standard deviation, which data set has the least standard deviation?

14. Select the letter of the appropriate data set. Without calculating the standard deviation, which data set has the greatest standard deviation?

15. Explain the reason for your decisions in questions 13 and 14.

16. Fish lengths. You study the lengths of fish in two lakes. Lake A has fish lengths with =18 inches and =2.6 inches and Lake B has fish with lengths, such that =18 inches and =1.5 inches. Which lake is more likely to have fish greater than 22 inches in length?

17. Cost of widgets follows a bell curve. The mean cost of a widget is $387, with a standard deviation of $19. Between what two values do about 68% of the widgets cost?

Coefficient of variation. The coefficient of variation (CV) is an alternate way to measure variation. The CV expresses the standard deviation as a percent of the mean. Because it has no unit of measure, you can use the coefficient of variation to compare the variability of data with different units of measure. Note: Either the sample standard deviation, ss, or the population standard deviation, , may be used for calculating the CV. Use the appropriate value of the standard deviation depending on whether the data pertain to a population or a sample. CV=standard deviation / Mean 100%

18. Find the coefficient of variation for the data set given in Table 4 (Round your answer to 3 decimal places).

Section 2.5

19. True or False? If a data set has Q1=321, Q2=389 and 7Q3=457, then a data value of 650 would be considered an outlier.

20. True or False? 75% of the data in a data set with quantitative data lie between Q1 and the maximum datum value.

Problems 22-25. Use the data in Table 4 to answer the questions.

21. What is Q1?

22. What is Q2?

23. What is Q3?

24. Draw a box-and-whisker plot that represents the data set in Table 4. (Note: When drawing the box-and-whisker plot, please label the 5-number summary values. If you are doing a hand sketch, use an appropriate scale and use graph paper.)

25. What is the IQR?