The ages of Ritika and Animesh are in the ratio of 7 : 9 respectively. After 6 years the ratio of their ages will be 4 : 5. What is the difference in their present ages?

Correct option is A

Given:

The present age ratio of Ritika and Animesh is 7: 9.

After 6 years, the ratio of their ages will be 4 : 5.

Solution:

Let the present ages of Ritika and Animesh be 7x and 9x, where x is a constant.

After 6 years, their ages will be 7x + 6 and 9x + 6.

Use the given ratio for their ages after 6 years:

​$$\frac{7x + 6}{9x + 6} = \frac{4}{5}$$​

5(7x + 6) = 4(9x + 6)

35x + 30 = 36x + 24

x = 6

Ritika's present age = 7x = 7 × 6 = 42

Animesh's present age = 9x = 9 × 6 = 54

Difference in their present ages:

54 - 42 = 12

The difference in their present ages is 12 years.