Two students appeared at an examination. One of them secured 9 marks more than the other and his marks was 56% of the sum of their marks. The marks obtained by them are:
Aptitude
Percentage
Difficulty: Easy
Choose an option
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A39, 30
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B41, 32
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C42, 33
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D43, 34
Answer
Correct Answer: 42, 33
Explanation
### Concept & Logic
Translate the conditions of the word problem into a simple mathematical equation, or use the ratio of their marks derived from the given percentage.
Let the total marks of both students be $100\%$. If the higher scoring student gets $56\%$ of the total sum, the other student must have received $100\% - 56\% = 44\%$ of the sum.
### Step-by-Step Solution
* The difference in their percentage of the total marks is $56\% - 44\% = 12\%$.
* We are given that the difference in their actual marks is $9$.
* Therefore, $12\%$ of the total marks $= 9$.
* Total sum of marks $= \frac{9}{0.12} = \frac{900}{12} = 75$.
* The first student's marks $= 56\%$ of $75 = 0.56 \times 75 = 42$.
* The second student's marks $= 44\%$ of $75 = 0.44 \times 75 = 33$.
### Exam Strategy & Shortcut
**Option Elimination:** The fastest way to solve this in an exam is by testing the given options.
Take option (c): $42, 33$.
* Condition 1: Difference is $42 - 33 = 9$. (Satisfied)
* Condition 2: Sum is $42 + 33 = 75$. Is $42$ equal to $56\%$ of $75$?
* $0.56 \times 75 = 42$. (Satisfied)
Option (c) is the only one that works perfectly.
### Common Pitfall
A very common mistake is setting up the equation as $x = 0.56(x - 9)$ instead of making the $56\%$ apply to the **sum** of both marks. Always read carefully what the percentage is taken of.
### Final Answer
**Therefore, the correct answer is 42, 33.**