CA Foundation · Quantitative Aptitude · Ratio and Proportion, Indices and Logarithms
Two numbers are in the ratio 3 : 5. If 6 is added to each, the ratio becomes 2 : 3. The smaller number is:
The smaller number is 18. Taking the numbers as 3k and 5k, the condition (3k + 6)/(5k + 6) = 2/3 gives k = 6, so the numbers are 18 and 30. Adding 6 to each gives 24 and 36, which are in the ratio 2 : 3.
- A12
- B18Correct
- C9
- D15
Explanation
Let the numbers be 3k and 5k. Then (3k + 6)/(5k + 6) = 2/3, so 9k + 18 = 10k + 12, giving k = 6. The numbers are 18 and 30. Check: 24 : 36 = 2 : 3. The smaller number is 18.
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