The age of Manisha and Sudeshna are in the ratio of 5 : 6 respectively. After 8 years the ratio of their ages will be 7 : 8. What is the difference of their ages ?

A 6

B 4

C 15

D 9

Correct Answer: Option B

Let the age of Manisha and Sudeshna is 5x and 6x years respectively.

According to the given data,

5x+8/6x+8 = 7/8

42x + 56 = 40x + 64

x = 4

Required Difference of their ages = (6 × 4) – (5 × 4)

= 4 years.