Question

A random sample of n = 11 observations was selected from a normal population. The sample...

A random sample of n = 11 observations was selected from a normal population. The sample mean and variance were x = 3.93 and s2 = 0.3216. Find a 90% confidence interval for the population variance σ2. (Round your answers to three decimal places.)

Homework Answers

Answer #1

Chi-square critical values at 0.10 significance level with 10 df = 3.940 , 18.307

90% confidence interval for 2is

(n-1) S2 / /2 <  2< (n-1) S2 / 1-/2

(11-1) * 0.3216 / 18.307 < 2< (11-1) * 0.3216 / 3.940

0.176 < 2< 0.816

90% CI is (0.176 , 0.816)

Know the answer?
Your Answer:

Post as a guest

Your Name:

What's your source?

Earn Coins

Coins can be redeemed for fabulous gifts.

Not the answer you're looking for?
Ask your own homework help question
Similar Questions
A sample of 235 observations is selected from a normal population with a population standard deviation...
A sample of 235 observations is selected from a normal population with a population standard deviation of 25. The sample mean is 20. Determine the standard error of the mean. (Round your answer to 3 decimal places.) Determine the 90% confidence interval for the population mean. (Use z Distribution Table.) (Round your answers to 3 decimal places.)
A sample of 245 observations is selected from a normal population with a population standard deviation...
A sample of 245 observations is selected from a normal population with a population standard deviation of 25. The sample mean is 20. Determine the standard error of the mean. (Round your answer to 3 decimal places.) Determine the 90% confidence interval for the population mean. (Use z Distribution Table.) (Round your answers to 3 decimal places.)
A sample of 23 observations is selected from a normal population where the sample standard deviation...
A sample of 23 observations is selected from a normal population where the sample standard deviation is 4.95. The sample mean is 16.90.   a. Determine the standard error of the mean. (Round the final answer to 2 decimal places.) The standard error of the mean is _______ . b. Determine the 90% confidence interval for the population mean. (Round the t-value to 3 decimal places. Round the final answers to 3 decimal places.) The 90% confidence interval for the population...
Consider a normal population with an unknown population standard deviation. A random sample results in x−x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x−x− = 62.88 and s2 = 16.81. [You may find it useful to reference the t table.] a. Compute the 90% confidence interval for μ if x−x− and s2 were obtained from a sample of 24 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 90% confidence...
A sample of 250 observations is selected from a normal population with a population standard deviation...
A sample of 250 observations is selected from a normal population with a population standard deviation of 23. The sample mean is 18. Determine the standard error of the mean. (Round your answer to 3 decimal places.) Determine the 99% confidence interval for the population mean. (Use z Distribution Table.) (Round your answers to 3 decimal places.)
Consider a normal population with an unknown population standard deviation. A random sample results in x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x− = 50.36 and s2 = 31.36. [You may find it useful to reference the t table.] a. Compute the 99% confidence interval for μ if x− and s2 were obtained from a sample of 16 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 99% confidence...
Assume a normal population with known variance σ2, a random sample (n< 30) is selected. Let...
Assume a normal population with known variance σ2, a random sample (n< 30) is selected. Let x¯,s represent the sample mean and sample deviation. (1)write down the formula: 98% one-sided confidence interval with upper bound for the population mean. (2) show how to derive the confidence interval formula in (1).
A sample of 10 observations is selected from a normal population for which the population standard...
A sample of 10 observations is selected from a normal population for which the population standard deviation is known to be 4. The sample mean is 24. (Round your answers to 3 decimal places.) (a) The standard error of the mean is . (c) The 99 percent confidence interval for the population mean is between ___ and ___.
A sample of 25 observations is selected from a normal population where the population standard deviation...
A sample of 25 observations is selected from a normal population where the population standard deviation is 32. The sample mean is 77.   a. Determine the standard error of the mean. (Round the final answer to 3 decimal places.) The standard error of the mean is . b. Determine the 95% confidence interval for the population mean. (Round the z-value to 2 decimal places. Round the final answers to 3 decimal places.) The 95% confidence interval for the population mean...
Consider a normal population with an unknown population standard deviation. A random sample results in x−x−...
Consider a normal population with an unknown population standard deviation. A random sample results in x−x− = 49.64 and s2 = 38.44. a. Compute the 95% confidence interval for μ if x−x− and s2 were obtained from a sample of 22 observations. (Round intermediate calculations to at least 4 decimal places. Round "t" value to 3 decimal places and final answers to 2 decimal places.) b. Compute the 95% confidence interval for μ if x−x− and s2 were obtained from...
ADVERTISEMENT
Need Online Homework Help?

Get Answers For Free
Most questions answered within 1 hours.

Ask a Question
ADVERTISEMENT