MATH 221 Week 5 Homework: Statistics for Decision-Making (Collection)

(MATH 221 Week 5 Homework)

MATH 221 Week 5 Homework (May 2021)

1. Question: From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 21.69 with a population standard deviation of 3.23. What is the 95% confidence interval for the amount of time spent on administrative issues?
2. Question: If a confidence interval is given from 43.83 up to 61.97 and the mean is known to be 52.90, what is the margin of error?
3. Question: If a computer manufacturer … a supplier that could produce parts that were very precise, what characteristics would be better?
4. Question: The 95% confidence interval for these parts is 56.98 to 57.05 under normal operations. A systematic sample is taken from the manufacturing line to determine if the production process is still within acceptable The mean of the sample is 56.96. What should … done about the production line?
5. Question: In a sample of 41 temperature readings taken from the freezer of a restaurant, the mean is 31.9 degrees and the population standard deviation is 2.7 degrees. What would be the 80% confidence interval for the temperatures in the freezer?
6. Question: What is the 99% confidence interval for a sample of 36 seat belts that have a mean length of 85.6 inches long and a population standard deviation of 2.9 inches?
7. Question: If two samples A and B had the same mean and standard deviation, but sample A had a larger sample size, which sample would have the wider 95% confidence interval?
8. Question: Determine the minimum sample size required when you want to be 95% confident that the sample mean is within one unit of the population mean. Assume a population standard deviation of 3.8 in a normally distributed
9. Question: In a sample of 14 CEOs, they spent an average of 12.9 hours each week looking into new product opportunities with a sample standard deviation of 4.9 hours. Find the 95% confidence interval. Assume the times are normally
10. Question: In a sample of 32 kids, their mean time on the internet on the phone was 29.1 hours with a population standard deviation of 6.4 hours. Which distribution would … most appropriate to use?
11. Question: Under a time crunch, you only have time to take a sample of 10 water bottles and measure their contents. The sample had a mean of 05 ounces with a sample standard deviation of 0.3 ounces. What would be the 90% confidence interval, when we … these measurements are normally distributed?
12. Question: Say that a supplier claims they are 99% confident that their products will be in the interval of 50.02 to 50.38. You take samples and find that the 99% confidence interval of what they are sending is 50.00 to 50.36. What conclusion can be made?
13. Question: In a sample of 28 cups of coffee at the local coffee shop, the temperatures were normally distributed with a mean of 162.5 degrees with a sample standard deviation of 16.7 degrees. What would … the 95% confidence interval for the temperature of your cup of coffee?
14. Question: In a situation where the sample size was … from 41 to 63, what would … the impact on the confidence interval?
15. Question: You needed a supplier that could provide parts as close to 76.8 inches in length as possible. You receive four contracts, each with a … level of accuracy in the parts supplied. Which of these four would you … most likely to accept?
    

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MATH 221 Week 5 Homework (v1)

1. Question: From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 21.69 with a population standard deviation of 3.54. What is the 95% confidence interval for the amount of time spent on administrative issues?
2. Question: If a confidence interval is … from 43.85 to 61.95 and the mean is known to … 52.90, what is the margin of error?
3. Question: If a shirt manufacturer wanted to make shirts that fit most individuals, what characteristics would … better?
4. Question: Which of the following are most likely to lead a wide confidence interval?
5. Question: If you were designing a study that would benefit from very disperse data points, you would want the input variable to have:
6. Question: The 95% confidence interval for these parts is 56.98 to 57.05 under normal operations. A systematic sample is taken from the manufacturing line to determine if the production process is still within acceptable levels. The mean of the sample is 57.06. What should … done about the production line?
7. Question: In a sample of 41 temperature readings taken from the freezer of a restaurant, the mean is 31.9 degrees and the population standard deviation is 2.7 degrees. What would … the 80% confidence interval for the temperatures in the freezer?
8. Question: What is the 99% confidence interval for a sample of 36 seat belts that have a mean length of 85.6 inches long and a population standard deviation of 2.9 inches?
9. Question: If two samples A and B had the same mean and sample size, but sample A had a larger standard deviation, which sample would have the wider 95% confidence interval?
10. Question: Why might a company use a higher confidence interval, such as 99%, rather than a lower confidence interval, such as 80%?
11. Question: Determine the minimum sample size required when you want to … 95% confident that the sample mean is within one unit of the population mean. … a population standard deviation of 3.8 in a normally distributed population.
12. Question: Determine the minimum sample size required when you want to … 99% confident that the sample mean is within 0.25 units of the population mean. … a population standard deviation of 2.9 in a normally distributed population.
13. Question: In a sample of 14 CEOs, they spent an average of 12.9 hours each week looking into new product opportunities with a sample standard deviation of 4.9 hours. Find the 95% confidence interval. … the times are normally distributed.
14. Question: In a sample of 31 kids, their mean time on the internet on the phone was 36.5 hours with a sample standard deviation of 8.3 hours. Which distribution would … most appropriate to use, when we assume these times are normally … ?
15. Question: Under a time crunch, you only have time to take a sample of 15 water bottles and measure their contents. The sample had a mean of 20.05 ounces with a sample standard deviation of 0.3 ounces. What would … the 90% confidence interval, when we … these measurements are normally distributed?
16. Question: Say that a supplier claims they are 99% confident that their products will … in the interval of 50.02 to 50.38. You take samples and find that the 99% confidence interval of what they are sending is 50.04 to 50.40. What conclusion can … made?
17. Question: Market research indicates that a new product has the potential to make the company an additional $1.6 million, with a standard deviation of $2.5 million. If these estimates were … on a sample of 8 customers from a normally … data set, what would … the 95% confidence interval?
18. Question: In a sample of 20 cups of coffee at the local coffee shop, the temperatures were normally distributed with a mean of 162.5 degrees with a sample standard deviation of 14.1 degrees. What would … the 95% confidence interval for the temperature of your cup of coffee?
19. Question: In a situation where the sample size from a normally distributed data set was decreased from 45 to 22, what would … the impact on the confidence interval?
20. Question: You … a supplier that could provide parts as close to 76.8 inches in length as possible. You receive four contracts, each with a … level of accuracy in the parts supplied. Which of these four would you … most likely to accept?
    

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MATH-221 Week 5 Homework (v2)

1. Question: From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 20.53 with a population standard deviation of 3.23. What is the 95% confidence interval for the amount of time spent on administrative issues?
2. Question: If a confidence interval is … from 43.83 up to 61.97 and the mean is known to … 52.90, what is the margin of error?
3. Question: If a car manufacturer wanted lug nuts that fit nearly all the time, what characteristics would … better?
4. Question: Which of the following are most likely to lead to a narrow confidence interval?
5. Question: If you were designing a study that would benefit from very disperse data points, you would want the input variable to have:
6. Question: The 95% confidence interval for these parts is 56.98 to 57.05 under normal operations. A systematic sample is taken from the manufacturing line to determine if the production process is still within acceptable levels. The mean of the sample is 56.99. What should … done about the production line?
7. Question: In a sample of 41 temperature readings taken from the freezer of a restaurant, the mean is 31.9 degrees and the population standard deviation is 2.7 degrees. What would … the 80% confidence interval for the temperatures in the freezer?
8. Question: What is the 99% confidence interval for a sample of 36 seat belts that have a mean length of 85.6 inches long and a population standard deviation of 2.5 inches?
9. Question: If two samples A and B had the same mean and sample size, but sample B had a larger standard deviation, which sample would have the wider 95% confidence interval?
10. Question: Why might a company use a lower confidence interval, such as 80%, rather than a high confidence interval, such as 99%?
11. Question: Determine the minimum sample size required when you want to … 95% confident that the sample mean is within two units of the population mean. Assume a population standard deviation of 4.3 in a normally distributed population:
12. Question: Determine the minimum sample size … when you want to … 99% confident that the sample mean is within 0.50 units of the population mean. Assume a population standard deviation of 1.4 in a normally distributed population.
13. Question: In a sample of 10 CEOs, they spent an average of 12.9 hours each week looking into new product opportunities with a sample standard deviation of 4.9 hours. Find the 95% confidence interval. Assume the times are normally …
14. Question: In a sample of 32 kids, their mean time on the internet on the phone was 29.1 hours with a population standard deviation of 6.4 hours. Which distribution would … most appropriate to use?
15. Question: Under a time crunch, you only have time to take a sample of 10 water bottles and measure their contents. The sample had a mean of 20.05 ounces with a sample standard deviation of 0.3 ounces. What would … the 90% confidence interval, when we … these measurements are normally … ?
16. Question: Say that a supplier claims they are 99% confident that their products will … in the interval of 50.02 to 50.38. You take samples and find that the 99% confidence interval of what they are sending is 50.01 to 50.39. What conclusion can … made?
17. Question: Market research indicates that a new product has the potential to make the company an additional $1.6 million, with a standard deviation of $2.5 million. If these estimates were … on a sample of 12 customers from a normally distributed data set, what would … the 95% confidence interval?
18. Question: In a sample of 28 cups of coffee at the local coffee shop, the temperatures were normally … with a mean of 162.5 degrees with a sample standard deviation of 16.7 degrees. What would … the 95% confidence interval for the temperature of your cup of coffee?
19. Question: In a situation where the sample size was 28 while the population standard deviation was increased, what would … the impact on the confidence interval?
20. Question: You needed a supplier that could provide parts as close to 76.8 inches in length as possible. You receive four contracts, each with a promised level of accuracy in the parts supplied. Which of these four would you … most likely to accept?
    

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MATH 221 Week 5 Homework (v3)

1. Question: From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 20.53 with a population standard deviation of 3.54. What is the 95% confidence interval for the amount of time spent on administrative issues?
2. Question: If a confidence interval is … from 43.83 up to 61.97 and the mean is known to … 52.90, what is the margin of error?
3. Question: If a grocery store purchases paper bags from a company, they want them generally the same, but don’t want to pay extra for precision. What characteristics would … better?
4. Question: Which of the following are most likely to lead to a narrow confidence interval?
5. Question: If you were designing a study that would benefit from a narrow range of data points, you would want the input variable to have:
6. Question: The 95% confidence interval for these parts is 56.98 to 57.05 under normal operations. A systematic sample is taken from the manufacturing line to determine if the production process is still within acceptable levels. The mean of the sample is 57.06. What should … done about the production line?
7. Question: In a sample of 65 temperature readings taken from the freezer of a restaurant, the mean is 31.9 degrees and the population standard deviation is 2.7 degrees. What would … the 80% confidence interval for the temperatures in the freezer?
8. Question: What is the 99% confidence interval for a sample of 36 seat belts that have a mean length of 85.6 inches long and a population standard deviation of 2.5 inches?
9. Question: If two samples A and B had the same mean and standard deviation, but sample A had a larger sample size, which sample would have the wider 95% confidence interval?
10. Question: Why might a company use a higher confidence interval, such as 99%, rather than a lower confidence interval, such as 80%?
11. Question: Determine the minimum sample size required when you want to … 95% confident that the sample mean is within two units of the population mean. Assume a population standard deviation of 3.8 in a normally distributed population.
12. Question: Determine the minimum sample size … when you want to … 99% confident that the sample mean is within 0.50 units of the population mean. Assume a population standard deviation of 2.9 in a normally distributed population.
13. Question: In a sample of 10 CEOs, they spent an average of 12.9 hours each week looking into new product opportunities with a sample standard deviation of 4.9 hours. Find the 95% confidence interval. Assume the times are normally distributed.
14. Question: In a sample of 31 kids, their mean time on the internet on the phone was 36.5 hours with a sample standard deviation of 8.3 hours. Which distribution would … most appropriate to use, when we assume these times are normally … ?
15. Question: Under a time crunch, you only have time to take a sample of 15 water bottles and measure their contents. The sample had a mean of 20.05 ounces with a sample standard deviation of 0.4 ounces. What would … the 90% confidence interval, when we … these measurements are normally … ?
16. Question: Say that a supplier claims they are 99% confident that their products will … in the interval of 50.02 to 50.38. You take samples and find that the 99% confidence interval of what they are sending is 50.01 to 50.39. What conclusion can … made?
17. Question: Market research indicates that a new product has the potential to make the company an additional $1.6 million, with a standard deviation of $2.0 million. If these estimates were based on a sample of 12 customers from a normally … data set, what would … the 95% confidence interval?
18. Question: In a sample of 28 cups of coffee at the local coffee shop, the temperatures were normally … with a mean of 162.5 degrees with a sample standard deviation of 16.7 degrees. What would … the 95% confidence interval for the temperature of your cup of coffee?
19. Question: In a situation where the sample size was increased from 41 to 63, what would … the impact on the confidence interval?
20. Question: You … a supplier that could provide parts as close to 76.8 inches in length as possible. You receive four contracts, each with a … level of accuracy in the parts supplied. Which of these four would you … most likely to accept?
    

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MATH-221 Week 5 Homework (v4)

1. Question: From a random sample of 58 businesses, it is found that the mean time the owner spends on administrative issues each week is 20.53 with a population standard deviation of 3.23. What is the 95% confidence interval for the amount of time spent on administrative issues?
2. Question: If a confidence interval is … from 43.85 up to 61.95 and the mean is … 52.90, what is the margin of error?
3. Question: If a computer manufacturer … a supplier that could produce parts that were very precise, what characteristics would … better?
4. Question: Which of the following are most likely to lead to a narrow confidence interval?
5. Question: If you were designing a study that would benefit from data points with high values, you would want the input variable to have:
6. Question: The 95% confidence interval for these parts is 56.98 to 57.05 under normal operations. A systematic sample is taken from the manufacturing line to determine if the production process is still within acceptable levels. The mean of the sample is 56.96. What should … done about the production line?
7. Question: In a sample of 57 temperature readings taken from the freezer of a restaurant, the mean is 29.6 degrees and the population standard deviation is 2.7 degrees. What would … the 80% confidence interval for the temperatures in the freezer?
8. Question: What is the 99% confidence interval for a sample of 52 seat belts that have a mean length of 85.6 inches long and a population standard deviation of 2.9 inches?
9. Question: If two samples A and B had the same mean and sample size, but sample A had a larger standard deviation, which sample would have the wider 95% confidence interval?
10. Question: Why might a company use a higher confidence interval, such as 99%, rather than a lower confidence interval, such as 80%?
11. Question: Determine the minimum sample size … when you want to … 95% confident that the sample mean is within two units of the population mean. Assume a population standard deviation of 3.8 in a normally distributed population.
12. Question: Determine the minimum sample size … when you want to … 99% confident that the sample mean is within 0.25 units of the population mean. Assume a population standard deviation of 2.9 in a normally distributed population.
13. Question: In a sample of 10 CEOs, they spent an average of 12.9 hours each week looking into new product opportunities with a sample standard deviation of 4.9 hours. Find the 95% confidence interval. … the times are normally …
14. Question: In a sample of 18 kids, their mean time on the internet on the phone was 28.6 hours with a sample standard deviation of 5.6 hours. Which distribution would … most appropriate to use, when we assume these times are normally … ?
15. Question: Under a time crunch, you only have time to take a sample of 10 water bottles and measure their contents. The sample had a mean of 20.05 ounces with a sample standard deviation of 0.3 ounces. What would … the 90% confidence interval, when we … these measurements are normally … ?
16. Question: Say that a supplier claims they are 99% confident that their products will … in the interval of 50.02 to 50.38. You take samples and find that the 99% confidence interval of what they are sending is 50.01 to 50.39. What conclusion can … made?
17. Question: Market research indicates that a new product has the potential to make the company an additional $1.6 million, with a standard deviation of $2.5 million. If these estimates were … on a sample of 12 customers from a normally … data set, what would … the 95% confidence interval?
18. Question: In a sample of 28 cups of coffee at the local coffee shop, the temperatures were normally … with a mean of 182.5 degrees with a sample standard deviation of 14.1 degrees. What would … the 95% confidence interval for the temperature of your cup of coffee?
19. Question: In a situation where the sample size from a normally … data set was … from 45 to 22, what would … the impact on the confidence interval?
20. Question: You needed a supplier that could provide parts as close to 76.8 inches in length as possible. You receive four contracts, each with a promised level of accuracy in the parts … Which of these four would you … most likely to accept?