At present, the ratio between the ages of Arun and Deepak is 4 : 3. After 6 years, Arun’s age will be 26 years. What is the age of Deepak at present?

Suppose the present age of Arun is 4x years

and that of Deepak is 3x years.

6 years hence, Arun’s age = 4x + 6 = 26

⇒ 4x = 26 – 6

$x=frac{20}{4}=5$

∴ Present age of Deepak = 3x = 15 years