Madhya Pradesh Police Exam Model Paper 6

Given: Number of total boys and girls $= 540$ The ratio of boys and girls is $5 : 4$ The total number of girls increase $= 20\%$ Explanation: Let the proportional ratio = x According to the question, $5x + 4x = 540$ $\Rightarrow 9x = 540$ $\Rightarrow x = 60$ So Boys = 5x = 5 × 60 = 300 Girls $= 4x = 4 \times 60 = 240$ Now, Girls increase $= 240 \times 20\% = 48$ Number of total girl $= 240 + 48 = 288$ The new ratio of boys and girls $= 300 : 288 = 25 : 24$ ∴ The new ratio of boys and girls is $25 : 24$ . Shortcut: Given: Number of total boys and girls = 540 The ratio of boys and girls is 5 : 4 The total number of girls increase = 20% Explanation: Number of boys $= 540 \times \left(\frac{5}{9}\right) = 300$ Number of girls = 540 - 300 = 240 Number of girls after increase of $20\% = 240 \times 120\% = 288$ The new ratio of boys and girls $= 300 : 288 = 25 : 24$ ∴ The new ratio of boys and girls is 25 : 24.