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Question
A father's age is three times the age of his child. After 12 years, twice the age of father will be 36 more than thrice the age of his child. Find his present age.
* Question modified
Solution
Let the present age of father = x years and that of his child = y years
After 12 years,
father's age = (x + 12) years
child's age = (y + 12) years
According to given information, we have
x = 3y ....(i)
Now, after 12 years
2(x + 12) = 3(y + 12) + 36
⇒ 2x + 24 = 3y + 36 + 36
⇒ 2x - 3y = 48 ....(ii)
⇒ 2(3y) - 3y = 48
⇒ 3y = 48
⇒ y = 16
⇒ x = 3 x 16
= 48
Thus, the present age of father is 48 years.
* Question modified.
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