Question

Suppose the math department chair at a large state university wants to estimate the average overall rating, out of five points, that students taking Introductory Statistics gave their lecturers on their end-of-term evaluations. She selects a random sample of 32 evaluations and records the summary statistics shown.

Sample size	Sample mean	Sample standard deviation	Population standard deviation	Standard error	Confidence level
?	?⎯⎯⎯	?	?	??⎯⎯⎯⎯	?
32	3.9102	1.0809	1.0213	0.1805	95%

The department chair determines the standard error using ?, the standard deviation calculated from all student evaluations submitted to her department. Assume the Statistics lecturers' ratings have the same standard deviation.

Use this information to find the margin of error and the lower and upper bounds of a 95% confidence interval for ?, the mean overall rating students gave their Introductory Statistics lecturers. Round your answers to the nearest hundredth.

Suppose the math department chair at a large state university wants to estimate the average overall rating, out of five points, that students taking Introductory Statistics gave their lecturers on their end-of-term evaluations. She selects a random sample of 32 evaluations and records the summary statistics shown.

Sample size	Sample mean	Sample standard deviation	Population standard deviation	Standard error	Confidence level
?	?⎯⎯⎯	?	?	??⎯⎯⎯⎯	?
32	3.9102	1.0809	1.0213	0.1805	95%

The department chair determines the standard error using ?, the standard deviation calculated from all student evaluations submitted to her department. Assume the Statistics lecturers' ratings have the same standard deviation.

Use this information to find the margin of error and the lower and upper bounds of a 95% confidence interval for ?, the mean overall rating students gave their Introductory Statistics lecturers. Round your answers to the nearest hundredth.

Complete the following sentence to state the interpretation of the department chair's confidence interval.

Margin of error =

Lower bound =

Upper bound =

The                                                              that the                                                              of the overall ratings given on

                                                             at the end of the term                                                             .

Answer Bank

Answer 1