Let Nikita’s age = x years ∴ Ankit's age =(2x−4)years x(2x–4)=240 ⇒2x2−4x−240=0 ⇒x2−2x−120=0 ⇒x2−12x+10x−120=0 ⇒x(x−12)+10(x−12)=0 ⇒(x−12)(x+10)=0 ⇒x=12,‌or‌x=−10 ‌but‌x≠−10 ∴x=12 Hence Nikita’s age = 12 years.