The ratio of the present age of the two brothers is 11 : 13 and 6 years ago the ratio of their ages was 4 : 5. What will be the ratio of their ages after 5 years?
Show answer & explanation
Correct answer: C
Explanation
The correct answer is option 3 i.e. 27 : 31.
The ratio of the present age of the two brothers is 11 : 13.
Let the present ages of the two brothers are 11x and 13x.
The ratio of ages of the two brothers 6 years ago = 4 : 5
So, (11x - 6)/(13x - 6) = 4/5
⇒ 55x - 30 = 52x - 24
⇒ 55x - 52x = 30 - 24
⇒ 3x = 6
⇒ x = 6/3 = 2
The present age of the two brothers is 11x = 11 × 2 = 22 years and 13x = 13 × 2 = 26 years.
The ratio of their ages after 5 years = (22 + 5) : (26 + 5) = 27 : 31
Therefore, the ratio of age of the two brothers after 5 years is 27 : 31.