Question : Seven years ago, the ratio of the ages of A and B was 4 : 5. Eight years hence, the ratio of the ages of A and B will be 9 : 10. What is the difference between their present ages in years?
Option 1: 3
Option 2: 2
Option 3: 4
Option 4: 6
Correct Answer: 3
Solution :
Let the present ages of A and B as
From the problem,
Seven years ago, the ratio of the ages of A and B was 4 : 5.
Eight years hence, the ratio of the ages of A and B will be 9 : 10.
Solving these two equations simultaneously,
Therefore, the difference between their present ages = 22 - 19 = 3 years
Hence, the correct answer is 3.