Multiple choice

The ratio of the numbers of boys and girls in a college is 7 : 8. If the percentage increase in the numbers of boys and girls is 20% and 10%, respectively, what will be the new ratio?

  1. 17 : 18

  2. 8 : 9

  3. 10 : 11

  4. 21 : 22

  5. 22 : 21

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Let the number of boys at present = 7x and girls = 8x. After the percentage increment in number of boys and girls we will have:  Number of boys = 7x + 7x*(20/100) = 840x/100 and Number of girls = 8x + 8x*(10/100) = 880x/100 The ratio = (840x/100) : (880x/100) = 21 : 22. So, this is the correct answer.