Q6 of 80 Page 56

In class of 40 pupils the number of girls is three-fifths of the number of boys. Find the number of boys in the class.

Let the number of boys in the class be x.

∴ The number of girls in the class = .


The total number of pupils in the class = 40.


According to the given condition,



⇒ 3x + 5x = 200 (Multiplying throughout by 5)


8x = 200


⇒ x = (Transposing 8 to RHS)


x = 25


∴ The number of boys in the class is 25.


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