A father said to his son, 'n years back I was as old as you are now. My present age is four times your age n years back.' If the sum of the present ages of the father and the son is 130 years, what is the difference in their ages?
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A medium CSAT / General Aptitude multiple-choice question from UPSC Prelims 2024. Attempt it above, then check the correct answer and detailed explanation below.
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Correct answer: D. 36 years
By solving the system of equations derived from the conditions, the difference between the father's and son's ages is 36 years.
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