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Math125Week7BookExam.docxThe questions below are all multiple-choice, so work out your answers on a separate piece of paper and then select the correct choice. You can change your answer choices after selecting them. Good luck!
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1. Using the test scores in the table below, what is the mean score of the students who took the exam?
1. 85
2. 86
3. 87
4. 88
5. 89
2. Using the test scores in the table below, what is the median score of the students who took the exam?
1. 85
2. 86
3. 87
4. 88
5. 89
3. Using the test scores in the table below, what is the mode score of the students who took the exam?
1. 85
2. 86
3. 87
4. 88
5. 89
4. Using the test scores in the table below, which score represents the 30th percentile?
1. 85
2. 86
3. 87
4. 88
5. 89
5. Using the test scores in the table below, which score represents the 60th percentile?
1. 85
2. 86
3. 87
4. 88
5. 89
6. Using the test scores in the table below, what is the variance of the scores on the exam? (Round your answer to the nearest whole number.)
1. 18
2. 21
3. 24
4. 27
5. 31
7. Using the test scores in the table below, what is the standard deviation of the scores on the exam? (Round your answer to the nearest whole number.)
1. 3
2. 5
3. 6
4. 7
5. 9
8. Assume that 500,000 people take the GED exam (high school proficiency exam) each year and their scores form a normal distribution. If Tara scores one standard deviation above the mean, what percentile is she?
1. 34%
2. 68%
3. 84%
4. 95%
5. Not enough information to determine.
9. Assume that 500,000 people take the GED exam (high school proficiency exam) each year and their scores form a normal distribution. If Danny scores two standard deviations below the mean, what percentile is he?
1. 2.5%
2. 5.0%
3. 12.5%
4. 22.5%
5. Not enough information to determine.
10. Assume that 20 people take a math test, which is not enough for a normal distribution to form. If Conrad scores three standard deviations above the mean, what percentile is he?
1. 75.0%
2. 88.5%
3. 95.0%
4. 99.7%
5. Not enough information to determine.
11. Assume that 20 people take a math test, which is not enough for a normal distribution to form. If Sarah scores at the median, what percentile is she?
1. 34%
2. 50%
3. 68%
4. 95%
5. Not enough information to determine.
12. Assume that 20 people take a math test, which is not enough for a normal distribution to form. If Charlie scores at the mean, what percentile is he?
1. 44%
2. 50%
3. 56%
4. 68%
5. Not enough information to determine.
13. Compare the times of the two marathons runners in the table below. Which marathon runner is more likely to win the marathon on any given day?
1. Runner 1
2. Runner 2
3. They have the same likelihood of winning.
4. They have a different likelihood, but it cannot be determined who is more likely.
5. Not enough information to determine.
14. Compare the times of the two marathons runners in the table below. Which marathon runner has a higher variance in her performance?
1. Runner 1
2. Runner 2
3. They have the same variance.
4. They have a different variance, but it cannot be determined who has a higher variance.
5. Not enough information to determine.
15. Compare the times of two sprinters in the table below. Which sprinter is more likely to win the race on any given day?
1. Runner 1
2. Runner 2
3. They have the same likelihood of winning.
4. They have a different likelihood, but it cannot be determined who is more likely.
5. Not enough information to determine.
16. Compare the times of two sprinters in the table below. Which sprinter has a higher standard deviation in his performance?
1. Runner 1
2. Runner 2
3. They have the same standard deviation.
4. They have a different standard deviation, but it cannot be determined who has a higher standard deviation.
5. Not enough information to determine.
17. Typically, in the early stages of a country's transition from an emerging nation to a developed nation, death rates fall while birth rates stay constant. What type of covariance do death rates and birth rates have?
1. Positive Covariance
2. Negative Covariance
3. No Covariance
4. Inverse Covariance
5. Not enough information to determine.
18. Typically, in the middle stages of a country's transition from an emerging nation to a developed nation, death rates fall while birth rates fall. What type of covariance do death rates and birth rates have?
1. Positive Covariance
2. Negative Covariance
3. No Covariance
4. Inverse Covariance
5. Not enough information to determine.
19. Typically, in the late stages of a country's transition from an emerging nation to a developed nation, death rates stay constant while birth rates fall. What type of covariance do death rates and birth rates have?
1. Positive Covariance
2. Negative Covariance
3. No Covariance
4. Inverse Covariance
5. Not enough information to determine.
20. If a company’s profits increase when the economy slows, what type of covariance is there between this company and the broader economy?
1. Positive Covariance
2. Negative Covariance
3. No Covariance
4. Inverse Covariance
5. Not enough information to determine.
21. If the average height of a male in the U.S. is 70 inches and the standard deviation of male heights is 3 inches, what is the probability that a randomly selected male will be between 70 and 73 inches? (Assume a normal distribution.)
1. 18%
2. 34%
3. 50%
4. 68%
5. Not enough information to determine.
22. If the average height of a female in the U.S. is 65 inches and the standard deviation of female heights is 2.5 inches, what is the probability that a randomly selected female will be between 60 and 62.5 inches? (Assume a normal distribution.)
1. 5%
2. 14%
3. 18%
4. 24%
5. Not enough information to determine.
23. Using the information in questions 21 and 22, do men or women experience more variance in heights?
1. Men
2. Women
3. They experience the same variation in heights.
4. They exerpeince different variation, but it cannot be determined which experiences more variation.
5. Not enough information to determine.
24. A scientist has been studying antibiotic resistance in bacteria. She takes a random sample of bacteria and grows a culture of 1,000,000 bacteria. She then introduces an antibiotic and a week later, she finds that the culture contains 500,000 bacteria. She concludes that 50% of the bacteria have antibiotic resistance. Is she overestimating, underestimating or being accurate?
1. Underestimating because some resistant bacteria may have died naturally.
2. Underestimating because bacteria can grow at a slower rate than expected.
3. She is estimating accurately.
4. Overestimating because antiobiotic resitant bacteria will continue to replicate.
5. Overestimating because bacteria is rarelt antibotic resistant.
25. A political analyst is reviewing the data from a survey and is interested in understanding the correlation between age and candidate preference. He groups the respondents into the quintiles below and decides that there is no correlation. What is wrong with his analysis?
1. The analyst might not know all of the respondents' last names.
2. The analyst has assumed that the respondents have differing opinions.
3. The analyst should have grouped respondents by age.
4. The analyst is asking the wrong questions.
5. Quintiles is not a practical way to group respondents.
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