Question

The product of Shikha’s age five years ago and her age 8 years later is 30, her age at both times being given in years. Find her present age.

Answer 1

Let the present age of Shikha be ‘a’ years. 

Given, product of Shikha’s age five years ago and her age 8 years later is 30 

⇒ (a – 5)(a + 8) = 30 

⇒ a² + 3a – 40 – 30 = 0 

⇒ a² + 10a – 7a – 70 = 0 

⇒ a(a + 10) – 7(a + 10) = 0 

⇒ (a – 7)(a + 10) = 0 

⇒ a = 7 years