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The average marks of boys in a class is 52 and that of girls is 42 . The average marks of boys and girls combined is 50 . The percentage of boys in the class is

Options

  1. A40
  2. B20
  3. C80
  4. D60

Correct answer

C. 80

Step-by-step solution

52 x+42 y=50(x+y)2 x=8 y x y = 4 1 and x x+y = 4 5 % of boys =80 .

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