Question

Raju’s father is 4 times as old as Raju. After 5 years, father will be three times as old as Raju. Find their present ages.

Answer 1

RAJU=X
RAJU'S FATHER=4X

AFTER 5 YEARS
X+5=RAJU
4X+5=RAJU'S FATHER

SO,
4X+5=3(X+5)
4X+5=3X+15
4X-3X=15-5
1X=10
X=10
 
THERFORE 
RAJU'S AGE IS 10
RAJU'S FATHER AGE IS 40

Answer 2

Given:

Father = 4 Raju

After 5 years,

Father = 3 Raju

To find:

The present ages of Raju and Father

Solution:

Father + 5 = 3 Raju + 5

Substituting for father,

4 Raju + 5 = 3 ( Raju + 5 )

4 Raju + 5 = 3 Raju + 15

Solving for Raju,

Raju = 10 years.

Substituting,

We get,

Father = 4 ( 10 )

Hence,

Father = 40 years