Difficulty: Easy
Correct Answer: 200
Explanation:
Introduction / Context:This is a division-based approximation problem. The decimal numbers 4182.395 and 20.886 are close to round figures, so we can estimate quickly without a calculator. The goal is to convert to a simple mental-math division while keeping the ratio nearly the same.
Given Data / Assumptions:
Concept / Approach:When both numbers are near convenient round numbers, approximate each minimally so the ratio stays stable. Use 4182/20.9 or 4182/21 as quick proxies. Always sanity-check by multiplying a candidate answer by the divisor to see if we return near the dividend.
Step-by-Step Solution:
Use a tight rounding: 4182.395 ≈ 4182; 20.886 ≈ 20.9Compute 4182 ÷ 20.9 ≈ 200.1 (since 20.9 * 200 = 4180)Using the exact values gives about 200.25, still ≈ 200Verification / Alternative check:Multiply 200 * 20.886 = 4177.2 (slightly low). Adding one more unit (201) gives ≈ 4198.9 (slightly high). The true answer lies near 200.2, so 200 is the closest choice.
Why Other Options Are Wrong:
Common Pitfalls:Over-rounding both numbers in the same direction can distort the ratio. Keep the rounding tight and check by back-multiplying the candidate answer.
Final Answer:200
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