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The average marks obtained by the students in a class are 43 . If the average marks obtained by 25 boys are 40 and the average marks obtained by the girl students are 48 , then what is the number of girl students in the class?

Options

  1. A15
  2. B17
  3. C18
  4. D20

Correct answer

A. 15

Step-by-step solution

Number of girls student be x43= 25 40+x 48 x+25 aligned & 43 x+43 25=25 40+x 48 & 5 x=3 25 & x=15 aligned

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