Class A has 26 students with a mean mark of 63; class B has 34 students with a mean mark of 69. What is the mean mark of all the students?
Answer and explanation
Correct answer: C. 66.4
- Step 1: Total marks = 26x63 + 34x69 = 3984.
- Step 2: Mean = 3984/60 = 66.4.
Answer
66.4.
Why not the others: 66, 33.2 and 69.4 do not fit.
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