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In a class of 100 students there are 70 boys whose average marks in a subject are 75. If the average marks of the complete class is 72, then what is the average of the girls?

Options

  1. A73
  2. B65
  3. C68
  4. D74

Correct answer

B. 65

Step-by-step solution

Total student =100 ; for 70 stds 75 70=5250 7200-5250=1950 Average of girls = 1950 30 =65

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