Question

their present ages.
7. A father is three times as old as his son. In 12 years time, he will be twice as old as his son.
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 age will
be twice the sum of ages of two children. Find the age of father.
[CBSE 2003]

Answer 1

ASSALAMUALAIKUM

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Question 7

• Let the present age of son =x
• Then, the present age of father =3x

According to the question,

• The age of son after 12 years =x+12
• And the age of father after 12 years =2(x+12)

Therefore,

3x+12=2(x+12)

3x+12=2x+24

x=12

• So, the present age of son is 12 years and present age of father is 36 years.

Question 8

• 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

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INSHAALLAH it will help you !

Answer 2

Step-by-step explanation:

suppose son is x years old .

father =f = 3x

son =s= x

after 12 years

f = 3x+12

s=x+12

father will be twice of son

therefore 3x+12= (x+12) 2

3x+12 = 2x +24

3x-2x = 24- 12

x = 12

father's age = 3x

3 ×12

36