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:
(15.96)^2 ≈ 254.7216.75% of 285 = 0.75 * 285 = 213.75.Total ≈ 254.7216 + 213.75 = 468.4716.Nearest option: 470.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:
470
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