he Engineering department would like to know the difference between grades for students who prefer Marvel compared to DC. They assume the distribution of the two groups has the same standard deviation. They plan on using this to evaluate program candidates.
These means are totally random - not implying anything. Chill
From 68 students who said they preferred Marvel the average GPA was 3.6 with a standard deviation of 0.7.
From 91 students who said they preferred DC the average GPA was 2.89 with a standard deviation of 0.9.
The matched pairs standard deviation was 0.8.
Find an 89% confidence interval for the difference in GPA by taking the mean for Marvel minus the mean for DC.
