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The present age of father is three times the son's age. After 10 years the father will be twice the son's age. Son's present age is
A15 years
B5 years
C10 years
D20 years
Answer & Solution
Correct answer: C. 10 years
1. Let son = x; father = 3 x.
2. After 10 years: 3 x + 10 = 2(x + 10).
3. Solve: 3 x + 10 = 2 x + 20, so x = 10.
4. Son's present age is 10 years.
_Source: Selina Concise Mathematics Class 8, Ch 18 Linear Equations in One Variable (Mistral OCR'd PDF), section on age problems_
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