Difficulty: Medium
Correct Answer: 31
Explanation:
Introduction:
The original stem is ambiguous. Applying the recovery-first policy, interpret it so the total becomes a perfect cube: if there are n students and each pays n^2 rupees, then the total T = n * n^2 = n^3. This matches the provided total of 29,791 (which is 31^3).
Given Data / Assumptions:
Concept / Approach:
Use T = n^3. Take the cube root of 29,791 to find n.
Step-by-Step Solution:
T = n^3n = cube_root(29,791) = 31Check: 31^3 = 29,791
Verification / Alternative check:
If one instead assumed each pays n rupees, then T = n^2, but 29,791 is not a perfect square; thus the recovered assumption (n^2 per student) is consistent with the data.
Why Other Options Are Wrong:
30, 33, 40 do not satisfy n^3 = 29,791.
Common Pitfalls:
Misreading the contribution rule and treating 29,791 as a square instead of a cube; failing to apply the recovery-first interpretation to align with given total.
Final Answer:
31
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