Logical Reasoning and Analytical Ability
Logical Reasoning and Analytical Ability tests structured thinking rather than general knowledge: series, analogies, coding-decoding, blood relations, directions, syllogisms, seating arrangements, puzzles, data sufficiency, statement-assumption and Venn diagrams. Most questions reward a fixed method and careful reading.
Core rules
- Series: check differences, ratios, squares/cubes, alternating patterns, and letter positions (A=1 ... Z=26).
- Syllogism: draw minimal Venn diagrams; 'all A are B' does not convert to 'all B are A'; 'some A are B' converts to 'some B are A'.
- Blood relations: build a family tree with gender markers; count generations from the common ancestor.
- Directions: fix north and use right/left turns relative to facing direction; net displacement uses Pythagoras when paths are perpendicular.
- Seating: mark facing direction first; for circular arrangements, clockwise and anticlockwise change with facing.
Worked example
A person walks 5 km north, turns right and walks 3 km, then turns right and walks 5 km. How far and in which direction is he from the start? Reasoning: north 5 km and south 5 km cancel; the only remaining displacement is 3 km east. Answer: 3 km east.
Traps
- Converting 'some' into 'some not' without evidence.
- Forgetting that 'only a few' means some are and some are not.
- In circular seating, applying the same left/right rule to people facing the centre and facing outside.
- Solving puzzles from the first clue instead of using the most restrictive clue.
Key points are listed in the key_points field.