Class A has 19 students with a mean mark of 69; class B has 32 students with a mean mark of 85. What is the mean mark of all the students?
Answer and explanation
Correct answer: D. 79.039
- Step 1: Total marks = 19x69 + 32x85 = 4031.
- Step 2: Mean = 4031/51 = 79.039.
Answer
79.039.
Why not the others: 77, 39.52 and 82.039 do not fit.
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