Question

Age of a after 10 years will be twice the age that b had 10 years ago if a is 9 years elder than b then what is current age of b

Answer 1

Let the present age of b = x years
a is 9 years elder than b.
Therefore present age of a = x + 9 years

Age of a after 10 years = x + 9 + 10 = x + 19 years
Age of b before 10 years = x - 10 years

Given that the age of a after 10 years is twice as the age of b before 10 years
Therefore
x + 19 = 2(x - 10)
x + 19 = 2x - 20
2x - x = 20 + 19
x = 39 years

The present age of b = 39 years.

Hope this helps you.