Question

Father is 25 years older than his son. After 8 years, ratio of son's age to father's age will be 4/9. The son's present is age____________________​

Answer 1

Answer:

12 years

Step-by-step explanation:

let the age of son be x.

age of father = 25+x

After 8 years:-

age of son = x + 8

age of father = x + 25 + 8 = x + 33

ratio of their age = 4/9

x + 8/x + 33 = 4/9

after cross multiplication

9(x + 8) = 4(x + 33)

9x + 72 = 4x + 132

9x - 4x = 132 - 72

5x = 60

x = 12

so the present age of son = x = 12 years

the present age of father = x + 25 = 12 + 25 = 37 years

hope this helps

Answer 2

Answer:

• Son's present age is 12 years.

Step-by-step explanation:

Given that:

• Father is 25 years older than his son.
• After 8 years, ratio of son's age to father's age will be 4 : 9.

To Find:

• The son's present age.

Let us assume that:

• Son's age be x.

Then,

• Father's present age = (x + 25)

After 8 years,

• Son's age = (x + 8)
• Father's age = x + 25 + 8 = (x + 33)

As it is given that,

$\sf\longrightarrow\dfrac{x+8}{x+33}=\dfrac{4}{9}$

By cross-multiplication,

$\sf\longrightarrow 9(x+8)=4(x+33)$

Opening the brackets,

$\sf\longrightarrow 9x+72=4x+132$

Transposing variables and constants to LHS and RHS respectively and changing its sign,

$\sf\longrightarrow 9x-4x=132-72$

Solving further,

$\sf\longrightarrow 5x=60$

Transposing 5 from LHS to RHS and changing its sign,

$\sf\longrightarrow x=\dfrac{60}{5}$

Dividing 60 by 5,

$\sf\longrightarrow x=12$

Hence, x = 12.

Therefore, Son's present age is 12 years.