Question

In a family, the sum of the ages of four kids is 30 years less than the sum of the ages of their parents. In how many years will these sums be equal?

Answer 1

Explanation:

Let the sum of present ages of 4 kids be `A_k` years and sum of the present ages of their kids be `A_p` years.

By the problem

`A_p-A_k=30`

Let after `x` years these sums become equal.

After `x` years sum of ages of 4 kids will be `A_k+4x` years and that of parents will be `A_p+2x` years.

By the problem

`A_k+4x = A_p+2x`

`=>4x-2x = A_p-A_k`

`=>2x = 30`

`=>x = 30/2=15` years