Question

a father is now three times as an old as his son. Five years back, he was four times as old as his son. The ages of the son is​

Answer 1

Answer:

10

Step-by-step explanation:

let the age be x

so from given cond.

$\frac{3x}{5 + 4x} = \frac{x}{5 + x}$

$3x(5 + x) = x(5 + 4x)$

$15x + {3x}^{2} = 5x + {4x}^{2}$

$15x - 5x = {4x}^{2} - {3x}^{2}$

$10x = {x}^{2}$

now divide it by x

$10 = x$

therefore

$x = 10$

therefore age of his son is 10

Answer 2

Answer:

the age of son is 15

Step-by-step explanation:

take son age x, therefore father age 3x now

before 5 years the ages will be x-5, 3x-5

given, 3x-5 = 4(x-5)

then solve it, 3x-5 = 4x-20

4x-3x = 20-5, x= 15

so the age of son is 15