Difficulty: Easy
Correct Answer: 470
Explanation:
Introduction / Context:
This combines a squared decimal with a percentage of an integer. We compute each part accurately enough to pick the closest integer option.
Given Data / Assumptions:
Concept / Approach:
Calculate the square carefully, compute the percentage exactly, add them, and then round to the nearest choice if needed.
Step-by-Step Solution:
Verification / Alternative check:
Rounding the square to 255 would give 255 + 213.75 = 468.75, still near 470 and far from the other options, strengthening the choice of 470.
Why Other Options Are Wrong:
Common Pitfalls:
Approximating the square too coarsely (e.g., using 16^2 = 256 without recognizing the small reduction from 16 to 15.96), which can introduce a larger rounding error. Compute the square or use a close estimate like 16^2 minus a small correction.
Final Answer:
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