Question

The age of father 10 years ago was thrice the age of his son. ten years hence,father's age will be twice that of his son. what is the ratio of their presentages

Answer 1

Let before 10 years son's age = x,
then before 10 years father's age = 3x

Now son's age = x+10
father's age = 3x +10

therefore by given condition,
2×(x+10 +10 )= 3x+10 +10
or, 2x +40 =3x +20
or, x= 20

therefore present age of father = 70
& present age of son = 30

so, ratio of their present age
father : son = 7:3