Given: 10% of the boys are the same in number as 1/4 of the girls. Calculations: Let the number of boys and girls be 100x and 100y respectively 10% of the boys = 100x × 10/100 = 10x 1/4 th of the girls = 100y/4 = 25y According to the question 10x = 25y ⇒ x/y = 5/2 The number of boys = 100x ⇒ 100 × 5 = 500 The number of girls = 100y ⇒ 100 × 2 = 200 Ratio of boys to girls = 500 ∶ 200 = 5 ∶ 2 ∴ Ratio of boys to girls is 5 ∶ 2