Problem. Test scores for class are: 93%, 77%, 90%, 85%, 86%, 81%, 88%
At a = .10 can it be said that the standard deviation is greater than 4%. State (1) the null hypothesis (2) determine the critical value (3) determine the test statistic (4) State decision and summary
Also, construct the 90% confidence interval for the population standard deviation
Please show work and formulas.
The solution calculates the confidence intervals for test scores for class.