The ratio of Seema's age to the age of her mother is 5:12. The age difference is 21 years. What will be the ratio of Seema's age and her mother's age after three years?

Let ages of Seema and her mother be “5x” years and “12x” years respectively.

Difference between ages is 21 years

Hence,

12x - 5x = 21

7x = 21

x = 3

Therefore,

Age of Seema = 5 × 3 = 15 years

Age of her mother = 12 × 3 = 36 years

Ratio of ages after three years = ( 15+3 ) / (36+3 )

= 18 / 39

= 6 / 13

= 6 : 13