Question
The average marks scored by 30 boys and 40 girls are 75
and 85 respectively. Find the average marks scored by all the students together. (Answer should be rounded off to the nearest integer)Solution
ATQ, Required average = (30 X 75 + 40 X 85) ÷ (30 + 40) = (2,250 + 3,400) ÷ 70 = (5,650 / 70) ≈ 81
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