Reasoning Ability
What this domain tests
Reasoning Ability tests structured thinking under time pressure: puzzles and seating arrangements, syllogisms, blood relations, direction sense, coding-decoding, inequalities, order/ranking, input-output and data sufficiency.
Core rules and concepts
- Puzzles: build a grid or linear map; enter definite information first; keep alternative cases only while they remain possible.
- Syllogism: draw minimal Venn diagrams; a conclusion is valid only if it is true in every diagram consistent with the statements.
- Inequality: chain signs; A >= B > C gives A > C, but do not reverse a sign.
- Blood relations: convert statements into a family tree; use gender-specific symbols only when gender is stated.
- Coding-decoding: compare word-to-code pairs to isolate letter shifts or position rules.
Worked example
Statements: All pens are books. Some books are red. Conclusion I: Some pens are red. Conclusion II: Some books are pens. Reasoning: All pens are books means the pen set sits inside books. Some books are red says at least one book is red, but that red book need not be a pen. So Conclusion I is not guaranteed. Conclusion II is the converse of All pens are books in existential form: if pens exist, those pens are books, so some books are pens. Under standard bank-exam convention, Answer: only II follows.
Traps
- Converting All A are B into All B are A.
- Ignoring only a few or no qualifiers in syllogisms.
- Spending too long on one puzzle instead of solving its definite parts.
- Assuming gender in blood relations from a name.
- Overlooking either/or conclusions in inequality or syllogism.
Key points
Represent arrangements visually and test conclusions against the weakest possible diagram.