Difficulty: Easy
Correct Answer: 32
Explanation:
Introduction / Context:The position from the last (bottom-rank) is computed by subtracting the top-rank from the class size and then adding one—mirroring left/right conversions in rows.
Given Data / Assumptions:
Concept / Approach:Use bottom_rank = N − top_rank + 1.
Step-by-Step Solution:
bottom_rank = 49 − 18 + 1 = 32.Verification / Alternative check:If 17 students are ahead of Surbhi and 31 are behind, then from the last she is 32nd—consistent.
Why Other Options Are Wrong:31 or 35 arise from dropping/adding the “+1,” not from the correct identity.
Common Pitfalls:Confusing “from last” with “number behind.” Rank includes the student, so we add one.
Final Answer:32
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