1. A sample of 100 clients of an exercise facility was selected. Let X = the number of days per week that a randomly selected client uses the exercise facility.

X	Frequency
0	2
1	13
2	33
3	29
4	11
5	7
6	5

Find the number that is 1.5 standard deviations BELOW the mean. (Round your answer to three decimal places.)?

2. A survey of enrollment at 35 community colleges across the United States yielded the following figures.6414; 1550; 2109; 9350; 21828; 4300; 5944; 5722; 2825; 2044; 5481; 5200; 5853; 2750; 10012; 6357; 27000; 9414; 7681; 3200; 17500; 9200; 7380; 18314; 6557; 13713; 17768; 7493; 2771; 2861; 1263; 7285; 28165; 5080; 11622

Enrollment	Frequency
0 - 6,000	16
6,001 - 12,000	12
12,001 - 18,000	3
18,001 - 24,000	2
24,001 - 30,000	2

A school with an enrollment of 3,375 would be how many standard deviations away from the mean? (Round your answer to two decimal places.)?

3. One hundred teachers attended a seminar on mathematical problem solving. The attitudes of representative sample of 12 of the teachers were measured before and after the seminar. A positive number for change in attitude indicates that a teacher's attitude toward math became more positive. The twelve change scores are as follows.

3; 9;1; 1; 0; 4;3; 2;1; 5; 4;2

• Part (a)What is the mean change score? (Round your answer to two decimal places.)
• Part (b)What is the standard deviation for this sample? (Round your answer to two decimal places.)
• Part (c)What is the median change score? (Round your answer to one decimal place.)
• Part (d)Find the change score that is 2.2 standard deviations below the mean. (Round your answer to one decimal place.)

4. Forty randomly selected students were asked the number of pairs of sneakers they owned. Let X = the number of pairs of sneakers owned. The results are as follows.

X	Frequency
1	3
2	4
3	7
4	12
5	12
6	2

Find the sample standard deviation, s. (Round your answer to two decimal places.)

5. A music school has budgeted to purchase 3 musical instruments. They plan to purchase a piano costing $4,000, a guitar costing $600, and a drum set costing $700. The mean cost for a piano is $5,000 with a standard deviation of $2,000. The mean cost for a guitar is $500 with a standard deviation of $250. The mean cost for drums is $900 with a standard deviation of $125. (Enter your answers to two decimal places.) (a) How many standard deviations above or below the average piano cost is the piano?

____ standard deviations below the average (b) How many standard deviations above or below the average guitar cost is the guitar?

____ standard deviations above the average (c) How many standard deviations above or below the average drum set cost is the drum set?

____ standard deviations below the average