Correct Answer - Option 3 : 15

Let the age of Amit be 'x' years.

Age of Arjun = x + 6 years

Ratio of the ages of Amit and Arjun is 5 : 7

Therefore,

x/x + 6 = 5/7

⇒ 7x = 5(x + 6)

⇒ 7x = 5x + 30

⇒ 2x = 30

⇒ x = 15

Amit's age is 15 years.

Hence, **15** is the correct answer.