Five boys in a row – who stands in the middle? Rules: C stands at the extreme right. D is to the right of E. B is to the left of E but to the right of A (A … B … E). Determine the boy in the exact middle position.
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AB
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BC
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CD
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DE
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EA
Answer
Correct Answer: E
Explanation
Introduction / Context:This is a 5-seat single-row ordering problem with an extreme fixed (C at far right) and two relational constraints. We must identify the central (3rd) seat occupant.
Given Data / Assumptions:
- C is at the extreme right (seat 5).
- D is to the right of E ⇒ E … D.
- A … B … E (B is left of E but right of A).
Concept / Approach:With C fixed at 5, fit A, B, E, D into seats 1–4 while respecting A < B < E and E < D. Only one linearization satisfies all constraints without conflict.
Step-by-Step Solution:
Place E at seat 3 and D at seat 4 to satisfy E … D and leave room for A and B to the left.Then A at seat 1 and B at seat 2 fulfill A … B … E.Final arrangement (left→right): 1 A, 2 B, 3 E, 4 D, 5 C.Therefore, the middle (seat 3) is E.Verification / Alternative check:Trying E at seat 4 would force D at 5, which conflicts with C fixed at 5. Any other placements violate either A … B … E or E … D.
Why Other Options Are Wrong:A, B, C, D do not occupy the central seat in any valid arrangement.
Common Pitfalls:Forgetting that “extreme right” is absolutely fixed, leaving too few slots for E and D.
Final Answer:E