Question

If ratio of mohan's age to that of his father is 1 : 5. after 10 years, their ages will be in the ratio of 1 : 3. what is the father's present age?

Answer 1

Given: ratio of mohan's age to that of his father is 1 : 5

Let  Mohan's age be x then father's will be 5x.

After 10 years Mohan's age will be x+10 and father's age will be 5x+10.

THe ratio of  their ages after 10 years  is 1 : 3.

$\frac{x+10}{5x+10}=\frac{1}{3}.$

Cross multiplying we have:

3(x+10)=1(5x+10)

Or,3x+30=5x+10

30-10=5x-3x.

20=2x

Or x=10.

Father's age =5x=5(10)=50

Mohan's age = 10 years and Father's age is 50 years.