Difficulty: Easy
Correct Answer: 25 days
Explanation:
Introduction / Context:This is a standard “work (or stock) × time = constant” problem. When consumption per person is fixed, the total stock measured in person-days stays constant.
Given Data / Assumptions:
Concept / Approach:Use person-days: total stock = persons × days (at fixed per-person consumption).
Step-by-Step Solution:Total stock in person-days = 250 * 33.With 330 students, days available = (250 * 33) / 330.Compute: 250/330 = 25/33, so days = (25/33) * 33 = 25 days.
Verification / Alternative check:Scale up students by factor 330/250 = 1.32; therefore days scale down by 1/1.32 ≈ 0.7576; 0.7576 * 33 ≈ 25.
Why Other Options Are Wrong:20, 28, 30, and 22 days contradict the constant person-day relationship under identical per-student consumption.
Common Pitfalls:Using grams directly or changing serving size (which is stated constant) instead of using person-day balance.
Final Answer:25 days
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