The sum of the ages of Jayant, Prem and Paras is 93 years. Ten years ago, the ratio of their ages was 2 : 3 : 4. What is the present age of Paras?
Aptitude
Problems on Ages
Difficulty: Medium
Choose an option
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A24 years
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B28 years
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C32 years
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D34 years
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E38 years
Answer
Correct Answer: 38 years
Explanation
### Concept & Logic
To use a past ratio, you must adjust the present sum to match the past timeframe. Subtract the elapsed time for *each* person involved before distributing the total according to the ratio.
$$ \text{Past Sum} = \text{Present Sum} - (n \times \text{years}) $$
### Step-by-Step Solution
* **Given:** Present sum = 93. Ratio 10 years ago = $2:3:4$. Number of people = 3.
* **Calculation:** Find the sum of their ages 10 years ago.
* Past sum = $93 - (3 \times 10) = 93 - 30 = 63$ years.
* 10 years ago, their ages were $2x, 3x$, and $4x$.
* Equation: $2x + 3x + 4x = 63 \implies 9x = 63 \implies x = 7$.
* Paras's ratio share 10 years ago was $4x$.
* Paras's age 10 years ago = $4 \times 7 = 28$ years.
* Paras's present age = $28 + 10 = 38$ years.
### Exam Strategy & Shortcut
**Option Alignment:** The question asks for the present age of Paras. Since his ratio 10 years ago was 4, his (Present Age - 10) must be a multiple of 4.
Check the options:
(a) $24 - 10 = 14$ (No)
(b) $28 - 10 = 18$ (No)
(c) $32 - 10 = 22$ (No)
(d) $34 - 10 = 24$ (Yes)
(e) $38 - 10 = 28$ (Yes)
We have two candidates. But 34 implies $x=6$, making past sum 54, which doesn't match 63. So 38 is the only correct answer.
### Common Pitfall
Finding the age 10 years ago (28) and forgetting to add 10 to get the *present* age. Examiners frequently put 28 in the options as a trap (Option B).
### Final Answer
Therefore, the correct answer is **38 years**.