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Question
The age of the father is twice the sum of the ages of his two children. After 20 years, his age will be equal to the sum of the ages of his children. Find the age of the father.
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Solution
Let the present age (in year) of father and his two children be x, y and z years, respectively.
Now by given condition,
x = 2(y + z) ......(i)
And after 20 years,
(x + 20) = (y + 20) + (z + 20)
⇒ y + z + 40 = x + 20
⇒ y + z = x – 20
On putting the value of (y + z) in equation (i), we get the present age of father
x = 2(x – 20)
∴ x = 2x – 40
⇒ x = 40
Hence, the father’s age is 40 years.
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