2. Tinu is younger than Pinky by three
years. The product of their ages is 180. Find their ages.
Sol. Pinky's age be ‘x’ years
∴ Tinu's age is (x - 3) years [Given]
As per the given condition,
x (x – 3 ) = 180
∴ x2 – 3x = 180
∴ x2 – 3x – 180 = 0
∴ x2 -15x +12x - 180 = 0
∴ x(x – 15) +12 (x – 15) = 0
∴ (x – 15) (x + 12) = 0
∴ x – 15 = 0 or x + 12 = 0
∴ x = 15
or x = - 12
∵ x is age of a person
∴ x cannot be negative.
∴ x = 15
∴ x – 3 = 15 – 3 = 12
∴ The ages of Tinu is 12 years and that of Pinky is 15 years.
