A father is now four times as old as his son. In 6 years he will be three times as old as his son will be then. How old is the father now?
Answer and explanation
Correct answer: B. 48 years
- Step 1: Let the son be s now, so the father is 4s. In 6 years: 4s + 6 = 3(s + 6).
- Step 2: 4s + 6 = 3s + 18 gives s = 12, so the father is 48.
Answer
48 years.
Why not the others: Each other pair fails the second condition: for example 36 and 9 give 42 and 15, which is not a 3 : 1 ratio.
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