Data InsightsGraphs & Tables

Free GMAT Graphs & Tables Practice Question

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Five trade schools in rows; columns: enrollment, completion rate (percent), placement rate (percent), instructors. Sortable.
School	Enrollment	Completion rate (%)	Placement rate (%)	Instructors
Forgepoint	400	60	85	25
Brightline	1,200	50	70	80
Sterling	300	80	78	20
Hawthorne	600	70	82	40
Vantage	500	75	88	25

The table shows five trade schools: enrollment, the completion rate, the percentage of enrolled students who finish the program, the placement rate, the percentage of graduates placed in jobs, and the number of instructors. The table can be sorted by any column. For each statement, select Yes if it must be true based only on the data shown; otherwise select No.

(1) The completion rate across all enrolled students combined is below the simple average of the five schools' completion rates: . (2) The school with the largest enrollment also has the most students per instructor: . (3) The school with the highest completion rate also has the highest placement rate: .

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Answer & Explanation

Correct answer

1: Yes · 2: No · 3: No

The combined completion rate is not the simple average of the five rates; it has to be weighted by enrollment.

Statement 1 - Yes. The simple average of the five completion rates is (60 + 50 + 80 + 70 + 75) ÷ 5 = 67%. The rate across all students combined weights each school by its enrollment: (400 × 60 + 1,200 × 50 + 300 × 80 + 600 × 70 + 500 × 75) ÷ 3,000 = 187,500 ÷ 3,000 = 62.5%. The combined rate is lower, so the statement is true. The reason is that the largest school, Brightline with 1,200 students, has the lowest completion rate at 50%, so it dominates the pooled rate and pulls it below the simple mean. The trap is to average the five rates and stop.

Statement 2 - No. Students per instructor is enrollment divided by instructors: Forgepoint 16.0, Brightline 15.0, Sterling 15.0, Hawthorne 15.0, Vantage 20.0. The largest school is Brightline at 15.0 students per instructor, which is tied for the lowest; the most students per instructor is Vantage at 20.0, a much smaller school with 500 students. So the largest school is not the most crowded per instructor, and the statement is false. The trap is to assume the biggest school must have the most students per instructor.

Statement 3 - No. The highest completion rate is Sterling at 80%, but the highest placement rate is Vantage at 88%; Sterling's placement is 78%, the lowest of the five. The two leaders are different schools, so the statement is false. The trap is the halo assumption that the school best at finishing students is also best at placing them.

The lesson: a combined rate is weighted by size, a per-instructor figure can invert the enrollment ranking, and one school need not lead on two rates at once. Correct answers: Yes / No / No.