business stat final 4 pages

Confidence Interval for the Proportion

Business Major

Out of 20 schools, we have 16 private schools. So and.

The 90% confidence interval is given by

This means that we are 90% confident that the true proportion of private schools who major in business lies in this interval.

Out of 20 schools, we have 11 private schools. So and.

The 90% confidence interval is given by

This means that we are 90% confident that the true proportion of private schools who major in engineering lies in this interval.

Confidence interval for mean

Business major

The mean for this category is and sample standard deviation is .

The sample size is 20. C.I is given by

This means that we are 95% confidence that the Annual ROI for business major lies in the interval 7.31% and 8.33%.

Engineering Major

The mean for this category is 9.15 and sample standard deviation is 0.0146.

The sample size is 20. C.I is given by

This means that we are 95% confidence that the Annual ROI for engineering major lies in the interval 8.47% and 9.88%.