Question

A father is 3 times as old as his son. after 12 years his age will be twice as that of his son then. find their present ages?

Answer 1

Answer:

Present age of father = 36 years

Present age of son = 12 years

Step-by-step explanation:

Let present age of father be x years and present age of son be y years.

It is given that, father is three times as old as his son,

•°• x = 3y...........(1)

Age of father after 12 years = x + 12 years

age of son after 12 years = y + 12 years

It is also given that, after 12 years age of father will be as twice as that of his son.

•°• (x+12) = 2(y+12)

=> x + 12 = 2y + 24

=> x - 2y = 24 - 12

=> x - 2y = 12...............(2)

Put the value of (1) in (2).

=> 3y - 2y = 12

=> y = 12

•°• Present age of son = 12 years,

Put y = 12 in (1)

=> x = 3 ( 12 )

=> x = 36

•°• Present age of father = 36 years

Answer 2

$\bf{\Huge{\boxed{\underline{\sf{ANSWER\::}}}}}}$

$\bf{\Large{\underline{\sf{Given\::}}}}$

A father is 3 times as old as his son, after 12 years his age will be twice as that of his son.

$\bf{\Large{\underline{\sf{To\:find\::}}}}$

Their present ages.

$\bf{\Large{\underline{\tt{\green{Explanation\::}}}}}$

Let the present age of father be R years.

Let the present age of son be M years.

According to the question :

$\implies\sf{R=3M..................(1)}$

$\bf{\Large{\boxed{\sf{After\:12\:years\::}}}}}$

$\implies\sf{(R+12)=2(M+12)}\\\\\\\implies\sf{R+12=2M+24}\\\\\\\implies\sf{R-2M=24-12}\\\\\\\implies\sf{R-2M=12...................(2)}$

Putting the value of equation (1) in equation (2), we get;

$\implies\sf{3M-2M=12}\\\\\\\implies\sf{\purple{M=12\:years}}$

Now,

Putting the value of M in equation (1), we get;

$\implies\sf{R\:=\:3(12)}\\\\\\\implies\sf{R\:=\:(3*12)years}\\\\\\\implies\sf{\purple{R\:=\:36\:years}}$

Hence,

The Present age of father is 36 years.

The Present age of son is 12 years.