MATH 225N Week 6 Assignment Confidence Interval for Mean Population Standard Deviation Known

MATH 225N Week 6 Assignment: Confidence Interval for Mean Population Standard Deviation Known

1. Question: The lengths, in inches, of adult corn snakes are normally distributed with a population standard deviation of 8 inches and an unknown population mean. A random sample of 25 snakes is taken and results in a sample mean of 58inches. Identify the parameters … to calculate a confidence interval at the 99% confidence level. Then find the confidence interval.
2. Question: Lengths, in inches, of adult corn snakes are normally distributed with a population standard deviation of 8 inches and an unknown population mean. A random sample of 25 snakes is … and results in a sample mean of 58inches. What is the correct interpretation of the confidence interval?
3. Question: Suppose the germination periods, in days, for grass seed are normally distributed. If the population standard deviation is 3 days, what minimum sample size is … 90% confident that the sample mean is within 1day of the true population mean?
4. Question: Suppose the finishing times for cyclists in a race are normally distributed. If the population standard deviation is 16minutes, what minimum sample size is … to be 90% confident that the sample mean is within 5minutes of the true population mean?
5. Question: The weights, in pounds, of dogs in a city are normally distributed with a population standard deviation of2 pounds and an unknown population mean. A random sample of 16 dogs is taken and results in a sample mean of 28pounds. Identify the parameters … to calculate a confidence interval at the 90% confidence level. Then find the confidence interval.
6. Question: The weights, in pounds, of dogs in a city are normally distributed with a population standard deviation of 2 pounds and an unknown population mean. A random sample of 16 dogs is taken and results in a sample mean of 28pounds.
7. Question: What is the correct interpretation of the confidence interval? Suppose the weights, in pounds, of the dogs in a city are normally distributed. If the population standard deviation is 3pounds, what minimum sample size is needed to be 95% confident that the sample mean is within 1pound of the true population mean?
8. Question: Suppose the scores of a standardized test are normally distributed. If the population standard deviation is 4 points, what minimum sample size is needed to be 95% confident that the sample mean is within 1 point of the true population mean?
9. Question: The population standard deviation for the scores of a … test is 5 points. If we want to … 95% confident that the sample mean is within 2 points of the true population mean, what is the minimum sample size that should be taken?
10. Question: Suppose the heights of seasonal pine saplings are normally distributed. If the population standard deviation is 14 millimeters, what minimum sample size is … to be 95% confident that the sample mean is within 4millimeters of the true population mean?
    

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MATH 225N Week 6 Assignment: Confidence Interval for Mean Population Standard Deviation Known

1. Question: The population standard deviation for the number of corn kernels on an ear of corn is 94 If we want to … 90%confident that the sample mean is within 17kernels of the true population mean, what is the minimum sample size that should … taken?
2. Question: Suppose the scores of a standardized test are … If the population standard deviation is2 points, what minimum sample size is … 90% confident that the sample mean is within 1 point of the true population mean?
3. Question: The length, in words, of the essays written for a contest are … with a population standard deviation of 442words and an unknown population mean. If a random sample of 24 essays is … and results in a sample mean of 1330 words, find a 99% confidence interval for the population mean.
4. Question: The lengths, in inches, of adult corn snakes are … with a population standard deviation of 8inches and an unknown population mean. A random sample of 25 snakes is … and results in a sample mean of 58 Identify the parameters … calculate a confidence interval at the 99% confidence level. Then find the confidence interval.
5. Question: The lengths, in inches, of adult corn snakes are … with a population standard deviation of8 inches and an unknown population mean. A random sample of 25 snakes is … and results in a sample mean of 58  What is the correct interpretation of the confidence interval?
6. Question: The weights, in pounds, of dogs in a city are … with a population standard deviation of 2pounds and an unknown population mean. A random sample of 16 dogs is … and results in a sample mean of 28 Identify the parameters … calculate a confidence interval at the 90% confidence level. Then find the confidence interval….. You may use a calculator or the common z values above. Round the final answer to two decimal places.
7. Question: The weights, in pounds, of dogs in a city are … with a population standard deviation of2 pounds and an unknown population mean. A random sample of 16 dogs is … and results in a sample mean of 28 pounds….. What is the correct interpretation of the confidence interval?
8. Question: Suppose heights of dogs, in inches, in a city are … and have a known population standard deviation of 7inches and an unknown population mean. A random sample of 15dogs is … and gives a sample mean of 34 Find the confidence interval for the population mean with a 99% confidence level….. z0.10       z0.05   z0.025 z0.01   z0.005… 1.282  1.645            1.960   2.326            2.576…. You may use a calculator or the common z values above. Round the final answer to two decimal places.
9. Question: The germination periods, in days, for grass seed are … with a population standard deviation of5 days and an unknown population mean. If a random sample of 17 types of grass seed is … and results in a sample mean of 52days, find a 80% confidence interval for the population mean.
10. Question: Suppose scores of a standardized test are … and have a known population standard deviation of 6points and an unknown population mean. A random sample of 22 scores is … and gives a sample mean of 92 Identify the parameters … calculate a confidence interval at the 98% confidence level. Then find the confidence interval….. You may use a calculator or the common z values above.
11. Question: Suppose scores of a standardized test are … and have a known population standard deviation of6 points and an unknown population mean. A random sample of 22 scores is … and gives a sample mean of 92 points….. What is the correct interpretation of the 98% confidence interval?
12. Question: Suppose the heights of seasonal pine saplings are … If the population standard deviation is 14millimeters, what minimum sample size is … 95%confident that the sample mean is within 4 millimeters of the true population mean?… 101.282z0.051.645z0.0251.960z0.012.326z0.0052.576 ….. Use the table above for the z-score, and … sure to round up to the nearest integer.
13. Question: The population standard deviation for the scores of a standardized test is4  If we want to … 90% confident that the sample mean is within 1 point of the true population mean, what is the minimum sample size that should … ?…. z0.101.282z0.051.645z0.0251.960z0.012.326z0.0052.576….. Use the table above for the z-score, and … sure to round up to the nearest integer.
    

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MATH 225N Week 6 Assignment: Confidence Interval for Mean Population Standard Deviation Known

1. Question: Suppose the germination periods, in days, for grass seed are … If the population standard deviation is 3 days, what minimum sample size is … 90% confident that the sample mean is within 1 day of the true population mean?
2. Question: The length, in words, of the essays written for a contest are … with a population standard deviation of 442 words and an unknown population mean. If a random sample of 24 essays is … and results in a sample mean of 1330 words, find a 99% confidence interval for the population mean.
3. Question: The lengths, in inches, of adult corn snakes are … with a population standard deviation of 8 inches and an unknown population mean. A random sample of 25 snakes is … and results in a sample mean of 58….. Identify the parameters … calculate a confidence interval at the 99% confidence level. Then find the confidence interval.
4. Question: The lengths, in inches, of adult corn snakes are .. with a population standard deviation of 8 inches and an unknown population mean. A random sample of 25 snakes is … and results in a sample mean of 58…. What is the correct interpretation of the confidence interval?
5. Question: Suppose the scores of a standardized test are … If the population standard deviation is 2 points, what minimum sample size is … 90% confident that the sample mean is within 1 point of the true population mean?
6. Question: The weights, in pounds, of dogs in a city are … with a population standard deviation of 2 pounds and an unknown population mean. A random sample of 16 dogs is … and results in a sample mean of 28…. Identify the parameters … calculate a confidence interval at the 90% confidence level. Then find the confidence interval.
7. Question: The weights, in pounds, of dogs in a city are … with a population standard deviation of 2 pounds and an unknown population mean. A random sample of 16 dogs is … and results in a sample mean of 28…. What is the correct interpretation of the confidence interval?
8. Question: Suppose heights of dogs, in inches, in a city are … and have a known population standard deviation of 7 inches and an unknown population mean. A random sample of 15 dogs is … and gives a sample mean of 34 Find the confidence interval for the population mean with a 99% confidence level.
9. Question: The germination periods, in days, for grass seed are … with a population standard deviation of 5 days and an unknown population mean. If a random sample of 17 types of grass seed is … and results in a sample mean of 52 days, find a 80% confidence interval for the population mean.
10. Question: Suppose scores of a standardized test are … and have a known population standard deviation of 6 points and an unknown population mean. A random sample of 22 scores is … and gives a sample mean of 92….. Identify the parameters … calculate a confidence interval at the 98% confidence level. Then find the confidence interval.
11. Question: Suppose scores of a standardized test are … and have a known population standard deviation of 6points and an unknown population mean. A random sample of 22 scores is … and gives a sample mean of 92….. What is the correct interpretation of the 95% confidence interval?
12. Question: Suppose the heights of seasonal pine saplings are … If the population standard deviation is 14 millimeters, what minimum sample size is … 95% confident that the sample mean is within 4 millimeters of the true population mean?
13. Question: The population standard deviation for the scores of a standardized test is 4 If we want to … 90% confident that the sample mean is within 1 point of the true population mean, what is the minimum sample size that should … ?
14. Question: The population standard deviation for the total snowfalls per year in a city is 13 If we want to … 95% confident that the sample mean is within 3 inches of the true population mean, what is the minimum sample size that should … ?
15. Question: The population standard deviation for the lengths, in seconds, of the songs in an online database is 15 If we want to … 90% confident that the sample mean is within 4seconds of the true population mean, what is the minimum sample size that should … ?
16. Question: The population standard deviation for the number of corn kernels on an ear of corn is 94 If we want to … 90% confident that the sample mean is within 17 kernels of the true population mean, what is the minimum sample size that should … ?
17. Question: Suppose the weights, in pounds, of the dogs in a city are … If the population standard deviation is 3 pounds, what minimum sample size is … 95% confident that the sample mean is within 1 pound of the true population mean?
18. Question: Suppose the number of dollars spent per week on groceries is … If the population standard deviation is 7 dollars, what minimum sample size is … 90% confident that the sample mean is within 3 dollars of the true population mean?
19. Question: Suppose the speeds of vehicles traveling on a highway are … If the population standard deviation is 2 miles per hour, what minimum sample size is … 90% confident that the sample mean is within 1 mile per hour of the true population mean?
20. Question: A College Board sample estimated the standard deviation of 2016 SAT scores to … 194 You are researching the average SAT score. You want to know how many people you should survey if you want to know, at a 98% confidence level, that the sample mean SAT score is within 50 points of the true mean SAT score. What value for z should you use in the sample size formula? 
21. Question: You are researching the average SAT score, and you want to know how many people you should survey if you want to know, at a 98% confidence level, that the sample mean score is within 50 points of the true population mean. From above, we know that the population standard deviation is 194, and z01=2.326. What is the minimum sample size that should … surveyed? 
22. Question: A television network wants to estimate the average number of hours of TV watched each week by viewers.  The network decides to create a 95% confidence interval for the average number of hours of TV watched each week.  How large of a sample size of viewers should … to create this confidence interval if the television network wants to be 95% confident that the sample mean is within 1 hour of the population mean?  Assume the standard deviation for the number of hours of TV watched each week is 5. 97 viewers
23. Question: Suppose the number of square feet per house is … If the population standard deviation is 155 square feet, what minimum sample size is … 90% confident that the sample mean is within 47 square feet of the true population mean?
24. Question: The population standard deviation for the typing speeds for secretaries is 4 words per minute. If we want to … 90% confident that the sample mean is within 1 word per minute of the true population mean, what is the minimum sample size that should … ?
25. Question: The population standard deviation for the body weights of the employees of a company is 10 If we want to … 95% confident that the sample mean is within 3 pounds of the true population mean, what is the minimum sample size that should … ?
26. Question: The population standard deviation for the scores of a standardized test is 5 If we want to … 95% confident that the sample mean is within 2 points of the true population mean, what is the minimum sample size that should … ?
27. Question: Suppose the scores of a standardized test are … If the population standard deviation is 4 points, what minimum sample size is … 95% confident that the sample mean is within 1 point of the true population mean?
28. Question: The population standard deviation for the lengths, in words, of the essays written for a contest is 542 If we want to … 90% confident that the sample mean is within 141 words of the true population mean, what is the minimum sample size that should … ?
29. Question: Suppose the total snowfalls per year in a city are … If the population standard deviation is 13 inches, what minimum sample size is … 95% confident that the sample mean is within 4 inches of the true population mean?
30. Question: Suppose the finishing times for cyclists in a race are … If the population standard deviation is 16 minutes, what minimum sample size is … 90% confident that the sample mean is within 5 minutes of the true population mean?
31. Question: The population standard deviation for the number of pills in a supplement bottle is 16 If we want to … 95% confident that the sample mean is within 5 pills of the true population mean, what is the minimum sample size that should … ?