Reasoning: Puzzles, Syllogism and Deduction
The Reasoning domain tests logical structuring rather than mathematical ability: puzzles and seating arrangement, syllogism, inequality, coding-decoding, blood relations, direction sense, alphanumeric series and, in mains, input-output and data sufficiency.
Core rules
- Puzzles: build a table or circle from the definite clues first, then apply negative clues ("A is not next to B") as eliminations.
- Circular arrangement: facing the centre means left is clockwise; facing outward reverses it. Mark the facing direction before drawing.
- Inequality: a single symbol chain allows a direct conclusion; a conclusion that reverses a > or ≥ chain is invalid.
- Syllogism: draw Venn diagrams for each possibility; a conclusion is true only if it holds in every diagram.
Worked example
Statements: A ≥ B > C = D ≤ E. Conclusion I: A > D. The chain A ≥ B > C = D gives A > D - true. Conclusion II: C ≤ E. Since C = D and D ≤ E, C ≤ E - true. Both conclusions follow.
Traps
- In syllogism, "some A are not B" cannot be converted to "some B are not A".
- In circular seating, swapping inside/outside facing silently reverses every left-right clue.
- In blood relations, do not assume gender from a name; decode "brother of my father's only son" step by step.
- In coding-decoding, check letter-position shifts separately for vowels and consonants before assuming one rule.
- In inequality, conclusions using "either-or" need both a complementary pair and a missing definite relation.