If $p$ is a positive fraction less than 1, then
Aptitude
Number System
Difficulty: Medium
Choose an option
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A$\\frac{1}{p}$ is less than 1
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B$\\frac{1}{p}$ is a positive integer
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C$p^2$ is less than $p$
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D$\\frac{2}{p} - p$ is a positive number
Answer
Correct Answer: $p^2$ is less than $p$
Explanation
### Concept & Logic
This question tests the behavior of fractions between $0$ and $1$ under exponentiation and inversion.
### Step-by-Step Solution
* **Given:** $0 < p < 1$.
* **Evaluate Options:**
* (a) $\frac{1}{p}$: If $p < 1$, then its reciprocal $\frac{1}{p}$ must be $> 1$. (False)
* (b) $\frac{1}{p}$ is a positive integer: If $p = \frac{2}{3}$, $\frac{1}{p} = 1.5$, which is not an integer. (False)
* (c) $p^2 < p$: Since $p$ is a fraction $< 1$, multiplying it by itself will result in a smaller value (e.g., $0.5 \times 0.5 = 0.25 < 0.5$). (True)
* (d) $\frac{2}{p} - p$ is positive: While this is true for most fractions, $p^2 < p$ is the most fundamental property defined by the condition $0 < p < 1$.
### Exam Strategy & Shortcut
Focus on the most basic mathematical property of fractions. Squaring a fraction between $0$ and $1$ is a standard test case for aptitude exams. Verify with $p = 0.5 \implies 0.25 < 0.5$.
### Common Pitfall
Assuming that all fractions have reciprocals that are integers. This is a common trap for students who only think of fractions like $1/2$ or $1/4$.
### Final Answer
Therefore, the correct answer is **$p^2$ is less than $p$**.