Question

Father's age is three times the sum of ages of his two children. After 5 years his age will
be twice the sum of ages of two children. Find the age of father.
(CBSE 2003
T
ears later his ago​

Answer 1

Answer:

let his chidren's age =x

then father's age =3x

after 5 years his children will be =x+5

therefore father's age after 5 years = 2(x+5)

then 3x=2(x+5)

3x=2x +10

3x-2x = 10

x=10

thus the age of father =3x=3×10

=30

Answer 2

Let Present Age of 2 children is ='x'and 'y ' years Respectively

Age of Father is 3 times the Sum of age of His 2 children.

Father Present age=3(x+y) years

After 5 years

Father Age will be=3(x+y)+5 years

1st Children Age will be=(x+5) years

2nd Children age will be=(y+5) years

Now Father age will be also 2 times Ages of his Children after 5 years.

Means

Age of Father after 5 years=2×(sum of Age of 2 children after 5 years)

3(x+y)+5=2(x+5+y+5)

3x+3y+5=2x+10+2y+10

3x+3y+5=2x+2y+20

3x+3y-(2x+2y)=20-5

3x+3y-2x-2y=15

3x-2x+3y-2y=15

x+y=15

Age of Father 3(x+y)

=3×15

=45 years

Age of Father=45 years