Question

I the present age of A and B are in the ratio 7:5. 10 years later, their ages will be in the ratio 9:7. find their present ages.

Answer 1

let the age be x
present age of a =7x
present age of b =5x
ten years later
7x+10/5x+10=9/7
7(7x+10)=9(5x+10)
49x+70=45x+90
49x-45x=90-70
4x=20
x=20/4
x=5
present age of a =7*5=35
present age of b =5*5=25