An IQ test scoring is designed to have mean of 100 and astandard deviation of 15. The scores are known to be normallydistributed. A principal at a private school wants to investigatewhether the average IQ of the students at her school isstatistically different from the designed mean. She randomlysamples from the school and has 15 students take the IQ test. Theaverage test score of the sample is 95 and the sample standarddeviation is 2. Use α = .10
1. Follow the 7 steps for hypothesis testing to solve thisproblem using the critical region method.
2. Calculate the p value.
3. Calculate the 90% confidence interval. Look to see if thehypothesized mean is in confidence intervals.
4. Do you come to the same conclusion using critical region, pvalue and confidence intervals?
