TNPSC Group II · Bite-size lessons
Puzzles
About 7 min · Aptitude and Mental Ability · English
Time worked out from the lesson's 490 words at 150 words a minute, plus a minute for each question.
Puzzles form a time-consuming section in TNPSC aptitude papers. They test your ability to organize scattered information, eliminate contradictions, and arrive at a unique arrangement.
Key ideas
- Fixed vs. Variable Information: Always start with clues that give absolute positions ("A sits at the left end") before processing relative clues ("B sits two places from C"). Fixed points anchor your diagram.
- Linear Arrangement: People sit in a row facing one direction (or sometimes two rows facing each other). "Left of" and "right of" depend on whose perspective — always assume the viewer faces the row unless stated otherwise.
- Circular Arrangement: People sit around a table. "Clockwise" and "anticlockwise" matter. If all face the centre, immediate left = clockwise neighbour; if all face outward, it reverses.
- Scheduling Logic: Map days/time slots on one axis, persons/tasks on another. Each slot typically has one assignment. Look for "before," "after," "immediately after," "not on Monday" type clues.
- Grouping Constraints: Identify inclusion rules ("P and Q are in the same team") and exclusion rules ("R and S cannot be together"). Form mini-clusters first, then combine.
Watch out for
- Perspective Error: In linear rows, confusing "left of X" from the viewer's perspective vs. X's perspective. Fix: Unless stated, assume observer faces the row; left is viewer's left.
- Skipping Negative Clues: Ignoring "A is not adjacent to B" until the end, then realizing the arrangement violates it. Fix: List negative clues separately and check after every placement.
- Overcomplicating Circular Positions: Numbering circular seats inconsistently. Fix: Always label 1–8 (or 1–n) clockwise and stick to it throughout.
Quick reference
- Start with fixed/absolute clues; save relative clues for later.
- Draw diagrams — linear rows, circles, or grids — before attempting.
- "Opposite" in circular = n/2 seats away (e.g., 4 seats in an 8-person circle).
- "Between X and Y" usually means consecutive: X–?–Y.
- Two valid cases? Carry both forward; one will break.
Check yourself: 3 questions
1. Five friends — Arun, Bala, Chitra, Devi and Ezhil — are sitting in a row facing north. Arun sits at one of the ends. Chitra sits second to the right of Arun. Devi sits between Chitra and Ezhil. Who sits at the right end?
2. Six students — P, Q, R, S, T and U — are scheduled for interviews from Monday to Saturday, one student per day. P's interview is scheduled before R but after Q. S is interviewed on Wednesday. T is interviewed immediately after R. U is not interviewed on Monday. On which day is Q interviewed?
3. Seven employees of a company — Ajay, Bina, Charan, Divya, Ehsan, Fathima and Ganesh — work in three departments: Sales, Marketing and HR. At least two employees work in each department. Ajay and Bina work in the same department. Charan does not work in Marketing. Divya works in HR. Ehsan and Fathima work in different departments. Ganesh works in Sales. If Ehsan works in Marketing, then in which department does Bina work?
This lesson is cut from the topic's note, not rewritten. Fact-checked on 18 Oct 2026: an AI-assisted check of this note against cited sources; the errors it found were corrected that day. Some errors may remain. The questions are from Shishya's validated question bank.
Read the full noteFlashcards for this topic
Saves this lesson and its 3 questions in this browser on this phone. No sign-in; nothing about you is saved or sent. A saved copy is not updated until you save it again. Parts that load from the server when you use them (the AI tutor, adaptive practice, sign-in) still need a connection.