Question

The present age of a man is 4 times to that of his son. After 20 yr, his age will be twice to age of his son, then present age of his son is.​

Answer 1

Step-by-step explanation:

Let the age of son be x and the age of father be y.

Since, the age of father is 4 times to his son.

So,

y=4x ……. (1)

Since, the age of father is 2 times to his son after 16 years.

So,

y+16=2(x+16)

y+16=2x+32

y=2x+16 ……. (2)

From equation (1) and (2), we get

4x=2x+16

2x=16

x=8

And y=32

Hence, the age of son is 8 years and age of father is 32 years.

Answer 2

Given :

⬤ Present Age of a Man is 4 times that of his son .

⬤ After 20 years , his age will be twice to age of his son .

To Find :

⬤ Age of Son .

Solution :

Let :

• Age of Son be = x
• Age of Man be = 4x

After 20 years :

• Age of Son = x + 20
• Age of Man = 4x + 20

Now :

As given that , After 20 years , his age will be twice to age of his son . Hence ,

$\sf{4x+20=2(x+20)}$

4x + 20 = 2x + 40

4x - 2x = 40 - 20

2x = 20

x = 20/2

x = 10

Therefore , The Value of x is 10 .

So ,

Age of Son = x

= 10 years

Age of Man = 4x

= 4(10)

= 40 years

Hence , Age of Son is 10 years and Age of Man is 40 years .

Check :

4x + 20 = 2(x + 20)

4(10) + 20 = 2(10 + 20)

40 + 20 = 20 + 40

60 = 60

Hence Checked .