Question
Average marks scored by each boy in a class were 70,
whereas that by each girl were 80. If the number of boys is 50% more than the number of girls, then find the average score of each student.Solution
Let the number of girls = 2x.
Thus, the number of boys = 3x. Total marks of boys = 3x × 70 = 210x
Total marks of girls = 2x × 80 = 160x Total marks = 210x + 160x = 370x
Total students = 2x + 3x = 5x Average = 370x ÷ 5x = 74
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