A university health center tracks the number of flu-related visits during each month of the fall semester. The center director wonders whether students come down with the flu more often around midterm (mid-October) and final (mid December) exams. Can these data shed any light on this issue?

Flu-Related Visits to the University Health Center (by months)

September October November December

20 48 27 56

Is there any significant difference among the flu-related visits during the fall semester? Use an level of .05 to test the appropriate hypothesis.