Difficulty: Easy
Correct Answer: R < P < Q
Explanation:
Introduction / Context: This question examines decimal computation and comparison, including a small square, its reciprocal square, and a shifted square minus 1.
Given Data / Assumptions:
Concept / Approach: Compute each value exactly and then compare. Beware that squaring a small decimal gives a very small positive number, while the reciprocal square becomes large. A near-one square minus 1 will be negative.
Step-by-Step Solution:
P = (0.08)^2 = 0.0064Q = 1 / 0.0064 = 156.25(1 − 0.08) = 0.92 ⇒ 0.92^2 = 0.8464 ⇒ R = 0.8464 − 1 = −0.1536Ordering: R (−0.1536) < P (0.0064) < Q (156.25)Verification / Alternative check: Estimate check: 0.08^2 is clearly tiny positive; reciprocal square is very large; a number close to 1 squared then minus 1 is a small negative. The ordering matches intuition.
Why Other Options Are Wrong: Any option claiming P = R is false since P ≈ 0.0064 and R ≈ −0.1536. Options reversing the order ignore signs or magnitude.
Common Pitfalls: Misplacing decimal points; forgetting that reciprocals of numbers less than 1 are greater than 1; sign errors when subtracting 1.
Final Answer: R < P < Q
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