Question
Average marks scored by each boy in a class were 70,
whereas that by each girl were 90. If the number of boys in the class is 50% more than the number of girls in the class, then find the average score of each student (boys + girls).Solution
Let the number of girls be 2x.
Thus, the number of boys = 3x. Total marks of boys = 3x × 70 = 210x
Total marks of girls = 2x × 90 = 180x Total marks = 210x + 180x = 390x
Total number of students = 2x + 3x = 5x Average = 390x ÷ 5x = 78
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