AMC8 1990 Problem 9

The grading scale shown is used at Jones Junior High. The fifteen scores in Mr. Freeman’s class were: 89,72,54,97,77,92,85,74,75, 63,84,78,71,80,90.

In Mr. Freeman’s class, what percent of the

A: 93-100 students received a grade of \mathrm{C} ?

B: 85-92

C: 75-84

D: 70-74

F: 0-69

Answer Choices
A. 20 \%
B. 25 \%
C. 30 \%
D. 33 \dfrac{1}{3} \%
E. 40 \%