Unit 14
Ordering Deduction
About this unit
Place people, objects, or events in the correct order — or determine what must, could, or cannot be in a specific position — using a set of positional clues. Questions range from simple 4-person linear arrangements to complex 8-person circular seating, relay handovers, and multi-criteria ranking puzzles.
What types of questions will you face?
- 1Linear ordering: 4-6 people in a row with "left of", "right of", and "not at end" constraints
- 2Circular seating: 6-8 people around a table with "opposite", "adjacent", and relative-direction constraints
- 3Relay/handover chain: trace an object passing through a sequence of handovers at specific times
- 4Multi-criteria ranking: rank people by two criteria simultaneously (time AND score) using clues
- 5Partial ordering: given 3 facts about relative positions, determine what else MUST or CANNOT be true
- 6"Valid arrangement" questions: given 4 possible orderings, identify the one that satisfies all rules
Skills you will build
- Tracking multiple positional constraints (before/after, adjacent, not adjacent) simultaneously
- Building up valid arrangements step-by-step from the most constrained element first
- Applying "opposite in a circle" and "adjacent" rules for circular arrangements
- Tracing relay handover chains forward in time
- Determining what must be true vs. what could be true when the arrangement isn't fully fixed
- Using elimination to discard invalid arrangements quickly
By the end of this unit, you will be able to
- Solve any 4-8 person linear or circular arrangement puzzle
- Trace relay chains across time to find who holds an item at any point
- Determine fixed positions and free positions in a partially constrained arrangement
- Answer "must be true / cannot be true" ordering questions reliably under time pressure
Difficulty profile
The hardest unit by average score (3.82). Simple 3-4 element orderings with one chain are Easy; circular arrangements with 6-8 people and multiple constraint types, relay chains, and multi-criteria rankings are Very Difficult. Mastery here significantly boosts your overall TS score.
Exam tip: Ordering Deduction
Start with the person/item with the most constraints — they are easiest to place. Then use each placed element to constrain the remaining ones. For circular arrangements, fix one person's seat first (the one with a "directly opposite" clue) then fill in from there.
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