Question

Find the Present Age of the Father
The age of a man is 3 times the sum of the ages of his two sons. After 5 years his age will be double the sum of their ages. Find the present age of the father? Use unitary method for solving it.

Answer 1

Let Father's age = F, 1st Son's age = S1 and 2nd son's age = S2

We have two conditions given in the question.

F = 3(S1 + S2) = 3S1 + 3S2 -------------- (i)

After 5 years,
F + 5 = 2(S1+5+S2+5)
F = 2S1 + 2S2 +15 -------------- (ii)

Equating (i) and (ii), we get
3S1 +3S2 = 2S1 + 2S2 +15
S1+S2=15

Putting this value in (i), we get F = 45

So father's age is 45 years.