Data interpretationQuestion 513 of 550

Class A has 20 students with a mean score of 80. Class B has 30 students with a mean score of 70. What is the mean score of all the students in both classes?

  1. 75
  2. 76
  3. 74
  4. 72
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Correct answer: 74

The sum is 20 × 80 + 30 × 70 = 1600 + 2100 = 3700. The mean is 3700 ÷ 50 = 74. We cannot just average 80 and 70.

Test structure: ETEC guide to the GAT

Practice data interpretation

Questions last reviewed: 21 October 2026