Assignment
1. What is the variance of the following data? If necessary, round your answer to two decimal places.
600, 470, 170, 430, 300
A. 23,056
B. 22,123
C. 21,704
D. 20,365
2. What is the standard deviation of the following data? If necessary, round your answer to two decimal places.
600, 470, 170, 430, 300
A. 144
B. 145
C. 146
D. 147
3. What is the variance of the following data? If necessary, round your answer to two decimal places.
17, 13, 13, 22, 11, 20
A. 14
B. 15
C. 16
D. 17
4. What is the standard deviation of the following data? If necessary, round your answer to two decimal places.
17, 13, 13, 22, 11, 20
A. 7
B. 6
C. 5
D. 4
5. The curve is symmetric about the _____________.
A. mean
B. standard deviation
C. variance
D. range
6. What percentage of the data falls within 1 standard deviation of the mean?
A. 68%
B. 95%
C. 99%
D. 100%
7. What percentage of the data falls within 2 standard deviation of the mean?
A. 68%
B. 95%
C. 99%
D. 100%
8. The time required to finish a test in normally distributed with a mean of 40 minutes and a standard deviation of 8 minutes. What is the probability that a student chosen at random will finish the test in less than 48 minutes?
A. 84%
B. 2%
C. 34%
D. 16%
9. The average score on a standardized test is 750 points with a standard deviation of 50 points. What is the probability that a student scores more than 700 on the standardized test?
A. 84%
B. 2%
C. 34%
D. 16%
10. If 1,000 students take a test that has a mean of 40 minutes, a standard deviation of 8 minutes, and is normally distributed, how many would you expect would finish in less than 40 minutes?
A. 250
B. 500
C. 750
D. 1000
11. The time required to finish a test in normally distributed with a mean of 40 minutes and a standard deviation of 8 minutes. What is the probability that a student chosen at random will finish the test between 24 and 48 minutes?
A. 82%
B. 2%
C. 84%
D. 16%
12. If 1,000 students take a test that has a mean of 40 minutes, a standard deviation of 8 minutes, and is normally distributed, how many would you expect would finish in between 24 and 48 minutes?
A. 250
B. 500
C. 750
D. 820
13. The average score on a standardized test is 750 points with a standard deviation of 50 points. If 2,000 students take the test at a local school, how many students do you expect to score between 700 and 750 points?
A. 680
B. 700
C. 720
D. 740
14.
Suppose you have a normally distributed set of data pertaining to a standardized test. The mean score is 1000 and the standard deviation is 200. What is the z-score of 1600 point score?
A. 2.5
B. 3.0
C. 1.5
D. 0.5
15. Suppose you have a normally distributed set of data pertaining to a standardized test. The mean score is 1000 and the standard deviation is 200. What is the z-score of 450 point score?
A. 2.75
B. -2.75
C. 1.50
D. -1.50.