Homework answers / question archive / A random sample of size 36 is drawn from an x distribution

A random sample of size 36 is drawn from an x distribution

Math

Share With

---

A random sample of size 36 is drawn from an x distribution. The sample mean is 100.

 

1)   Suppose the x distribution has a population standard deviation of 30. Compute a 90% confidence interval for the population mean. What is the value of the margin of error?

 

 

2.    Suppose the x distribution has a population standard deviation of 20. Compute a 90% confidence interval for the population mean. What is the value of the margin of error?

 

 

 

3.    Suppose the x distribution has a population standard deviation of 10. Compute a 90% confidence interval for the population mean. What is the value of the margin of error?

 

 

4.    Compare the margins of error for the above three parts. As the standard deviation decreases, how does the margin of error change?

 

 

5.    Compare the lengths of the confidence intervals for the first three parts. As the standard deviation decreases, how do the lengths of the confidence intervals change?

 

 

 

 

 

 

 

A random sample is drawn from a population with standard deviation 12. The sample mean is 30.

 

 

6.    Compute a 95% confidence interval for the population mean based on a sample size of 49. What is the value of the margin of error?

 

 

 

 

 

 

 

 

 

7.    Compute a 95% confidence interval for the population mean based on a sample size of 100. What is the value of the margin of error?

 

 

 

 

 

 

 

 

 

8.    Compute a 95% confidence interval for the population mean based on a sample size of 225. What is the value of the margin of error?

 

 

 

 

 

 

 

 

 

9.    Compare the margins of error for the above three parts. As the sample size increases, how does the margin of error change?

 

 

 

 

 

10. Compare the lengths of the confidence intervals for 6-8. As the sample size increases, how do the lengths of the confidence intervals change?