Arrangement and Distribution

Arrangement and Distribution problems in LRDI involve organizing people, objects, or events into specific patterns (rows, circles, tables, floors, or categories) based on a given set of conditions. These are logic-intensive sets where clues must be pieced together step by step to arrive at a consistent arrangement.


Common Types of Arrangement and Distribution Problems

  1. Linear Arrangement

    • People/items are placed in a row (facing north/south or left/right).
    • Example: “A sits to the left of B, but right of C.”
  2. Circular/Polygonal Arrangement

    • People/items arranged around a circle or polygon, facing inward/outward.
    • Example: “X sits second to the right of Y, who faces the center.”
  3. Floor/Building Arrangement

    • People live on different floors of a building, with positional constraints.
    • Example: “A lives above B but below C.”
  4. Distribution Problems

    • Assigning people to categories (jobs, subjects, fruits, colors, etc.) with conditions.
    • Example: “Five friends each like a different fruit.”
  5. Hybrid Problems

    • Combination of arrangement + distribution.
    • Example: “Eight people sit around a table, each working in a different company.”

How to Solve Step by Step

  1. Draw a structure

    • Row, circle, table, or floor diagram to map placements.
  2. Place definite clues first

    • Start with fixed positions like “A sits at one end.”
  3. Use relative clues

    • Translate clues like “to the left of,” “two away from,” into diagram placements.
  4. Track negative clues

    • Mark restrictions (e.g., “X does not sit next to Y”).
  5. Cross-check consistency

    • Ensure all clues fit; if contradictions arise, restart with alternate casework.

Conceptual Tips and Common Mistakes

  • Direction traps: Facing north vs facing south flips left/right orientation.
  • Counting positions wrong: Always count inclusively/exclusively as per clue wording.
  • Multiple possibilities: Keep parallel cases alive until eliminated.
  • Mixing categories: In distribution problems, carefully track which attributes belong to whom.
  • Time management: These puzzles are lengthy—use elimination wherever possible.

Examples

Example 1 — Linear Arrangement

Six people A–F sit in a row. A is left of B, C is right of D, and E sits at one end.
Answer: One valid sequence is E – A – B – D – C – F.


Example 2 — Circular Arrangement

Eight friends sit around a circle facing center. X sits second to the right of Y, and Z is opposite Y.
Answer: Place Y first, then map X and Z accordingly → full circle solved.


Example 3 — Floor Arrangement

Five people live on floors 1 to 5. A lives above B, but below C. D is not on the top floor.
Answer: Possible order: B (1), A (2), C (3), D (4), E (5).


Example 4 — Distribution Puzzle

Four students study different subjects: Math, Physics, Chemistry, Biology.

  • A does not study Math.
  • B studies Biology.
  • C studies Physics.
    Answer: A = Chemistry, B = Biology, C = Physics, D = Math.