Correct Answer - Option 1 : 21 : 22
Given:
Ratio of the number of boys and girls in a college = 7 : 8
Percentage increase in the no of boys = 20%
Percentage increase in the no of girls = 10%
Calculation:
Let the number of boys and girls be 70a and 80a respectively.
Increased number of boys = 70a + 70a × 20/100 = 84a
Increased number of girls = 80a + 80a × 10/100 = 88a
∴ New ratio of boys and girls = 84a : 88a
⇒ 21 : 22