CA Foundation · Quantitative Aptitude · Equations
A father is currently 4 times as old as his son. In 6 years he will be 3 times as old as his son. Five years ago, the sum of their ages was what?
Five years ago the sum of their ages was 50. The son is 12 and the father 48, found from 4x + 6 = 3(x + 6).
- A30Correct
- B35
- C40
- D25
Explanation
Let son's age be x, father's 4x. Then 4x + 6 = 3(x + 6), so 4x + 6 = 3x + 18 and x = 12. Father is 48. Five years ago they were 7 and 43, summing to 50? Recheck: 12 − 5 = 7 and 48 − 5 = 43, total 50. So the correct value is 50, not among the stated options.
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