Rifat's age after 15 years will be 5 times his age 5 years back. What is the present age of Rifat?

Question: Rifat's age after 15 years will be 5 times his age 5 years back. What is the present age of Rifat?

Solution:
Let Rifat's present age be x years.
Then, Rifat's age after 15 years = (x + 15) years.
Rifat's age 5 years back = (x - 5) years.

Therefore,
x + 15 = 5(x - 5)
⇒ x + 15 = 5x - 25
⇒ 5x - x = 15 + 25
⇒ 4x = 40
⇒ x = 40/4 = 10
∴ x = 10

Hence, Rifat's present age = 10 years.