Question

after 10 years a will be twice the age of b before 10 years and now if the difference in 9 years between them. then what is the age of b after 10 years

Answer 1

a+10=2b
a=2b-10
a=9+b
9+b=2b-10
b=2b-10-9
b=2b-19
as we know,[2b-b=b]
b=19
a=[19*2]-10
  =38-10
  =28
 
age b after 10 years =b+10
                                 =19+10
                                 =29