One year ago, the ratio of the ages of A and B was 4 : 3. The ratio of their ages, after 7 years from now, will be 9 : 7. What is the present age (in years) of B?
Show answer & explanation
Correct answer: A
Explanation
The correct answer is Option 1 i.e. 49.
One year ago, the ratio of the ages of A and B was 4x : 3x
So, the ratio of their present age = 4x + 1 : 3x + 1
After 7 years the ratio of A and B = 9 : 7
⇒
⇒ 7(4x + 8) = 9(3x + 8)
⇒ 28x + 56 = 27x + 72
⇒ x = 16
So, the present age of B = 3x + 1 = 48 + 1 = 49 years