Civil Service Exam Reviewer · Ratio and Proportion · hard
The present ages of a father and his son are in the ratio 2 : 1. 2 years ago, the ratio was 16 : 7. What is the son's present age?
- 9 years
- 18 years
- 7 years
- 11 years
Answer
A. 9 years
Solution
Ages 2k and 1k: (2k − 2)/(1k − 2) = 16/7 → k = 9. Son = 1 × 9 = 9 years.
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