Please explain steps

7. A statistics teacher claims that, on the average, 9% of her students get a grade of A, 11% get a B, 52% get a C, 22% get a D, and 6% get an F. The grades ofa random sample of 100 students were recorded. The following table presents the results. Observed 2 16 51 25 6 Test the hypothesis that the grades follow the distribution claimed by the teacher. Use the 0.05 level of significance