If every 2 out of 3 readymade shirts need alterations in the collar, every 3 out of 4 need alterations in the sleeves, and every 4 out of 5 need it in the body, how many alterations will be required for 60 shirts?
Aptitude
Simplification
Difficulty: Easy
Choose an option
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A24
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B123
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C133
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D143
Answer
Correct Answer: 133
Explanation
### Concept & Formula
The problem requires computing the sum total of individual defects across three mutually exclusive components (collar, sleeves, body) for a given batch of items.
$$ \text{Total Alterations} = \text{Collar Alterations} + \text{Sleeves Alterations} + \text{Body Alterations} $$
### Step-by-Step Solution
* **Given:**
* Total shirts = $60$
* Collar alteration rate = $\frac{2}{3}$
* Sleeves alteration rate = $\frac{3}{4}$
* Body alteration rate = $\frac{4}{5}$
* **Calculation:**
* Alterations needed in the collar:
$$ \frac{2}{3} \times 60 = 40 $$
* Alterations needed in the sleeves:
$$ \frac{3}{4} \times 60 = 45 $$
* Alterations needed in the body:
$$ \frac{4}{5} \times 60 = 48 $$
* Total alterations required:
$$ \text{Total} = 40 + 45 + 48 = 133 $$
### Exam Strategy & Shortcut
Factor out the total volume of shirts to combine the fractional operations into a single step:
$$ \text{Total} = 60 \times \left( \frac{2}{3} + \frac{3}{4} + \frac{4}{5} \right) $$
$$ \text{Total} = 60 \times \frac{2}{3} + 60 \times \frac{3}{4} + 60 \times \frac{4}{5} = 40 + 45 + 48 = 133 $$
Since 60 is perfectly divisible by the denominators 3, 4, and 5, evaluating each term independently is exceptionally swift.
### Common Pitfall
A common misinterpretation is treating the fractions dependently (e.g., computing alterations on the remaining shirts left after the previous alteration). The question states "every 2 out of 3 readymade shirts...", meaning these proportions apply to the entire initial pool of 60 shirts independently.
### Final Answer
**Therefore, the correct answer is 133.**