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5. Arrangement and Seating Puzzles

CSS GSA — Paper 7, Part-II, Section VII, Sub-topic 5 (Arrangement and Seating Puzzles)

Past Paper Weightage

  • Very high — the single most frequently tested Analytical Reasoning format; almost guaranteed every year.

Shortcut Method (Always Follow This Order)

  1. List all people/items and all clues first — number the clues so you can reference them.
  2. Place the MOST restrictive clue first — clues that fix an absolute position ("C sits at one end," "D is in the middle") narrow the search space fastest; place these before relative clues ("B is right of A").
  3. Build "chained" clues into blocks — if clue 1 says "B is right of A" and clue 2 says "D is between B and E," treat A-B-D-E as one linked chain/block rather than four separate facts.
  4. Draw a table with numbered seats and slot in the fixed points and blocks, then fill remaining seats by elimination.
  5. Verify every clue against your final arrangement before finalizing — this catches most careless errors.

Worked Example (Linear Arrangement)

  • Five friends A, B, C, D, E sit in a row. Clues: (1) B sits immediately right of A. (2) C sits at one end. (3) D sits between B and E.
    • Step 1: Place the most restrictive clue: C is at an end — try seat 1 = C.
    • Step 2: Combine clues 1 and 3 into a chain: "A-B" (clue 1) plus "D between B and E" (clue 3) forces the connected order A-B-D-E.
    • Step 3: With C fixed at seat 1, the remaining seats 2–5 must hold the A-B-D-E chain in order: seat 2=A, 3=B, 4=D, 5=E.
    • Step 4: Verify: B right of A ✓, C at an end ✓, D between B and E ✓. Final arrangement: C-A-B-D-E.

Circular Arrangement — Extra Tip

  • For circular/round-table puzzles, fix ONE person's position arbitrarily first (since a circle has no fixed "start"), then place everyone else relative to that fixed person — this avoids the confusion of rotating reference points.
  • Remember "clockwise" and "counter-clockwise" are from the perspective of someone looking down at the table from above, unless the question states otherwise.

MCQ Traps

  • Placing clues in the order they're given (rather than most-restrictive-first) wastes time and increases errors — always scan all clues before starting to place anyone
  • In circular arrangements, "immediately left of X" and "immediately right of X" give different seats — don't mix them up

Self-Test Questions

  1. Four people P, Q, R, S sit around a circular table. Q sits immediately right of P. S sits opposite P. Find one valid seating and verify it against all clues.
  2. Six people sit in a row. Devise your own 4-clue puzzle (with at least one absolute-position clue) and solve it using the table method.

Past-Paper MCQs (FPSC)

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The FPSC MCQ papers you shared (2024 and 2025) had no direct arrangement question.

Past-Paper Questions with Answers (FPSC)

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Every question below appeared in the FPSC papers you shared; the year and question number are in each title. Answers are worked out by me.

  • CSS 2020 Q7(c): Five girls (A, B, C, D, E) and four boys (W, X, Y, Z) go on a trip in three cars. Rules: three per car; at least one boy and one girl in each car; A and D together; Z not with B or C. Distribute them. (5)
    1. Seat the fixed pair first, adding a boy: Car-1: A, D, W
    2. Z must avoid B and C, so put Z with the remaining girl E: Car-2: Z, E, X
    3. The rest form Car-3: B, C, Y
    4. Check: each car has 3 people with at least one boy and one girl; A and D together; Z is not with B or C
    • Other valid arrangements exist (e.g. swapping W, X and Y among cars), as long as the rules hold
  • CSS 2019 Q8(a): Seven piano students T, U, V, W, X, Y, Z perform one after another. Rules: X cannot be first or second; W cannot play until X has played; neither T nor Y is seventh; either Y or Z plays immediately after W; V plays immediately before or after U. If V plays first, which must be true? (5)
    1. V is first, so U must be second (V and U are adjacent)
    2. W must be after X, and a Y or Z must follow W immediately, so W cannot be seventh; X cannot be seventh either
    3. T and Y cannot be seventh, so Z plays seventh
    4. The others (T sixth, X third, T right after Y, W right after X) can each fail in some valid order, e.g. X3 W4 Y5 T6 Z7 or T3 X4 W5 Y6 Z7
    5. Answer: Z plays seventh
  • CSS 2016 Q12(b): Ahmad, Ali, Akbar, Nasir and Shehbaz go to cities V, W, X, Y, Z by bus, train, aeroplane, car and boat. Akbar went to Y by car; Ali to X by air; Nasir travelled by boat; Shehbaz by train. X and W have no bus service. The person who went to X did not use a boat. (i) How did Ahmad travel and where did he go? (ii) How did the person who went to X travel? (5)
    1. Four modes are fixed: Akbar (car), Ali (air), Nasir (boat), Shehbaz (train); so Ahmad went by bus
    2. X and W have no bus service, so Ahmad did not go to X or W; X is Ali's, so Ahmad went to V or Z
    3. (i) Ahmad: bus, to V or Z (the clues do not fix which; W goes to Nasir or Shehbaz)
    4. (ii) The person who went to X (Ali) travelled by aeroplane

CSS Exam Perspective

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  • Most repeated areas: grouping people into cars (2020), ordering puzzles with 'immediately after' rules (2019), mode-and-destination tables (2016)
  • Tip: fix the most restricted person first, tabulate what is certain, and check every rule at the end