Question

Father age in 3 times the sum of tha ages of histwo children.after 5 years his age will be twice of the sum of ages of two chlidren.find the age of father.

Answer 1

hey Mate!!

⇒Let the Father's age be x and the sum of 2 children's age be y.
⇒x = 3y
=x - 3y = 0 ----- eq.(1)

After 5 years, 
                  Father's age will be  x + 5 
                  and his 2 children's age will be y + 5(2)
            ⇒x + 5 = y + 5(2)
            ⇒x + 5 = 2(y + 10)
            ⇒x + 5 = 2y + 20
            ⇒x - 2y = 20 -5
            ⇒x - 2y = 15 ----------------- eq.(2)

  from eq (1) and (2),
                                  x - 3y = 0
                                 -x - 2y =15
                                 ---------------
                                 ⇒  y = 15
 
put y value in the equation, 
                                               x - 3y = 0
                                           ⇒ x - 3(15)= 0
                                            ⇒ x = 45
 Father's age is 45.