A simple random sample of electronic components will be selected to test for the mean lifetime in hours. Assume that component lifetimes are normally distributed with population standard deviation of 30 hours. How many components must be sampled so that a 99% confidence interval will have margin of error of 2 hours?
A simple random sample of electronic components will be selected to test for the mean lifetime...
Question 7 (4.2 points) A simple random sample of electronic components will be selected to test for the mean lifetime in hours. Assume that component lifetimes are normally distributed with population standard deviation of 20 hours. How many components must be sampled so that a 99% confidence interval will have margin of error of 6 hours? Write only an integer as your answer. Question 8 (5 points) Six measurements were made of the mineral content (in percent) of spinach, with...
Lifetime of electronics: In a simple random sample of 100 electronic components produced by a certain method, the mean lifetime was 125 hours. Assume that component lifetimes are normally distributed with population standard deviation - 20 hours. Round the critical value to no less than three decimal places. Part: 0/2 Part 1 of 2 (a) Construct a 90% confidence interval for the mean battery life. Round the answer to the nearest whole number. A 90% confidence interval for the mean...
*Please Answer All* 1. A sample of 210 one-year-old baby boys in the United States had a mean weight of 23.8 pounds. Assume the population standard deviation is 3.0 pounds. What is the upper bound of the 90% confidence interval for the mean lifetime of the components? Round to two decimals. 2. Efficiency experts study the processes used to manufacture items in order to make them as efficient as possible. One of the steps used to manufacture a metal clamp...
A simple random sample of size n is drawn. The sample mean, x, is found to be 19.4, and the sample standard deviation, s, is found to be 4.9. Click the icon to view the table of areas under the t-distribution. (a) Construct a 95% confidence interval about if the sample size, n, is 35. Lower bound: :Upper bound: (Use ascending order. Round to two decimal places as needed.) (b) Construct a 95% confidence interval about if the sample size,...
A simple random sample of size n is drawn. The sample mean, x, is found to be 19.4, and the sample standard deviation, s, is found to be 4.9. Click the icon to view the table of areas under the t-distribution. OC. The margin of error decreases. (c) Construct a 99% confidence interval about if the sample size, n, is 35. Lower bound: 17.14; Upper bound: 21.66 (Use ascending order. Round to two decimal places as needed.) Compare the results...
A simple random sample of size n is drawn. The sample mean, X, is found to be 17.9, and the sample standard deviation, s, is found to be 4.8. Click the icon to view the table of areas under the t-distribution. (a) Construct a 95% confidence interval about us if the sample size, n, is 34. Lower bound: upper bound: (Use ascending order. Round to two decimal places as needed.) (b) Construct a 95% confidence interval about if the sample...
A simple random sample of size n is drawn. The sample mean,x overbarx, is found to be 17.8 and the sample standard deviation, s, is found to be 4.4 (a) Construct a 95% confidence interval about μ if the sample size, n, is 35 Lower bound: ____ Upper bound: ______ (Use ascending order. Round to two decimal places as needed.) (b) Construct a 95% confidence interval about μ if the sample size, n, is 51 Lower bound: ____ Upper bound:...
simple random sample of size nis drawn. The sample mean, X, is found to be 18.3, and the sample standard deviations, is found to be 4.7 Click the icon to view the table of areas under the distribution a) Construct a 95% confidence interval about if the sample size, n, is 35 Lower bound: 16,60 Upper bound: 19.92 Use ascending order. Round to two decimal places as needed.) b) Construct a 95% confidence interval about if the sample size, n,...
A simple random sample with n=56 provided a sample mean of 21.0 and a sample standard deviation of 4.7 . a. Develop a 90% confidence interval for the population mean (to 1 decimal). b. Develop a 95% confidence interval for the population mean (to 1 decimal). c.Develop a 99% confidence interval for the population mean (to 1 decimal). d. What happens to the margin of error and the confidence interval as the confidence level is increased?
A simple random sample of size n is drawn. The sample mean, , is found to be 19.2, and the sample standard deviation, s, is found to be 4.6. Click the icon to view the table of areas under the t-distribution. (a) Construct a 95% confidence interval about u if the sample size, n, is 35. Lower bound: I; Upper bound: (Use ascending order. Round to two decimal places as needed.) (b) Construct a 95% confidence interval about u if...