Multiple choice

The age of Amersh and Arun are in the ratio of 11 : 13. After 7 year the ratio of their ages will be 20 : 23. What is the difference between their ages ?

  1. 4 year

  2. 7 year

  3. 6 year

  4. 5 year

  5. None of these

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Let Amersh's age = 11x, Arun's age = 13x. After 7 years: (11x+7)/(13x+7) = 20/23. Cross-multiplying: 23(11x+7) = 20(13x+7) gives 253x+161 = 260x+140, so 7x = 21, x = 3. Difference = 13x-11x = 2x = 6 years.