Question

The age of the father is twice the sum of the ages of his 2 children. After 20 year equal to the sum of the ages of his children. Find the age of father​

Answer 1

Given

The age of the father is twice the sum of the ages of his 2 children. After 20 year equal to the sum of the ages of his children.

To find

Find the age of father

Solution

Let the age of father be x then sum of ages of two children be y

According to the given condition

=> x = 2y ---(i)

After 20 years

=> x + 20 = y + 2 × 20

=> x + 20 = y + 40

=> x - y = 40 - 20

=> x - y = 20 ------(ii)

From (ii)

=> x - y = 20

=> 2y - y = 20 [using i ]

=> y = 20

By substitution method

substitute the value of y in (i)

=> x = 2y

=> x = 2 × 20 = 40

Hence,

The age of father = x = 40 year

And the sum of the ages of two children

And the sum of the ages of two children = y = 20 year