Difficulty: Easy
Correct Answer: 3400
Explanation:
Introduction / Context:
This approximation problem tests number sense and the ability to round sensibly to get a near-exact product quickly. By grouping close-to-integer factors and using small adjustments, you can arrive at a highly accurate estimate without long multiplication.
Given Data / Assumptions:
Concept / Approach:
Round each factor to a convenient nearby value, compute, and then refine if needed. Because options are spaced by 50–400, rounding to 27, 28, and 4.5 or using a tighter pair like 26.8 and 27.9 still lands very close to the exact product. Use compensations only if choices are close together.
Step-by-Step Solution:
Verification / Alternative check:
Use midpoint method: (26.823 * 27.923) ≈ 27.373 * 27.373 ≈ 749.3; then 749.3 * 4.5001 ≈ 3371.9. Again, closest to 3400.
Why Other Options Are Wrong:
Common Pitfalls:
Over-rounding one factor too far (e.g., 30) without compensating others can push the product well above the true range. Keep rounding balanced across factors.
Final Answer:
3400
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