Question

Find the present ages of father and the son.
8. Father's age is three times the sum of ages of his two children. After 5 years his
be twice the sum of ages of two children. Find the age of father.
(CBSE 2003]
9. Two years ago, a father was five times as old as his son. Two years later, his age will be
age will
than three times the age of than Dia

Answer 1

Answer:

a) Let the age of father be x years and sum of the ages of his children by y years.

After 5 years,

Father's age = (x + 5) years

Sum of ages of his children = (y + 10) years

From the given information, we have:

x = 3y ...(1)

and x + 5 = 2(y + 10)

 x - 2y = 15 ...(2)

From (1) and (2), we have,

3y - 2y = 15 = y = 15

x = 3y = 45

Father's age = 45 years

b)Let father age be x, his son age be y.

Before 2 years,

⇒(x−2)=5(y−2)−−−−−−−(1)

After 2 years 

⇒(x+2)=8+3(y+2)−−−−−−−−(2)

From (1) x−5y+8=0

From (2) 

⇒x+2−3y−6−8=0

⇒x−3y−12=0

Solving them 

⇒−2y+20=0

⇒y=10

When y=10,x=42

So the present a