The data shown represent the scores on a national achievement test for a group of 10th-grade students.

Question:

The data shown represent the scores on a national achievement test for a group of 10th-grade students. Find the approximate percentile ranks of these scores by constructing a percentile graph.
a. 220
b. 245
c. 276
d. 280
e. 300
Score Frequency
196.5–217.5........5
217.5–238.5 .......17
238.5–259.5 .......22
259.5–280.5 .......48
280.5–301.5 .......22
301.5–322.5 .......6