Difficulty: Easy
Correct Answer: 486
Explanation:
Introduction / Context:
Like other ratio-shift problems, we parameterize the original numbers, apply the given increment, and enforce the new ratio to solve for the scaling factor. Once the originals are known, compute their product directly.
Given Data / Assumptions:
Concept / Approach:
Set (2x + 9)/(3x + 9) = 3/4. Solve for x, then compute (2x)*(3x) as the product of the original pair.
Step-by-Step Solution:
Verification / Alternative check:
After adding 9 → 27 and 36; ratio 27 : 36 = 3 : 4, confirming the setup.
Why Other Options Are Wrong:
360, 432, 480, 512 are products derived from incorrect x or arithmetic errors when multiplying.
Common Pitfalls:
Forgetting to add 9 to both numbers or cross-multiplying incorrectly in the proportion.
Final Answer:
486
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