A study of 50 randomly selected students from a particular college who did not go to...

A study of 50 randomly selected students from a particular college who did not go to the campus Learning Center for statistics tutoring had a mean overall grade (at the end of the semester) of 68.41% with a standard deviation of 9.60%. The same study also found that 48 randomly selected students who did take advantage of the tutoring at the campus Learning Center had a mean overall grade of 79.25% with a standard deviation of 8.71%. The standard deviation for both populations (students who did not use the Learning Center’s tutoring, and those students who did use it) is assumed to be equal. Construct a 99% confidence interval for the difference of the mean overall grade of students who did not use the Learning Center minus the mean overall grade of students who did use it.

a. (-15.70%, -5.997%)

b. (-15.71%, -5.968%)

c. (-15.23%, -6.454%)

d. (-15.61%, -6.071%)

Expert Solution

orchestra answered 1 year ago

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