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Question
The age of the father is seven times the age of the son. Ten years later, the age of the father will be thrice the age of the son. Find their present ages.
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Solution
Let the present age of father = x years and that of son = y years
After 10 years,
father's age = (x + 10) years
son's age = (y + 10) years
According to given information, we have
x = 7y ....(i)
And,
(x + 10) = 3(y + 10)
⇒ x + 10 = 3y + 30
⇒ x - 3y = 20
⇒ 7y - 3y = 20 ...[From (i)]
⇒ 4y = 20
⇒ y = 5
⇒ x = 7 x 5
= 35
Thus, the present age of son is 5 years and that of father is 35 years.
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* Question modified
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