Logical Reasoning
Logical Reasoning
CMAT's 20 logical reasoning questions split into puzzle sets (linear and circular seating, floor and scheduling puzzles, distribution) and standalone items - syllogisms, blood relations, direction sense, coding-decoding, series, inequalities, data sufficiency and short critical reasoning (assumption, inference, strengthen/weaken, cause-effect). Puzzle sets reward a clean grid drawn on paper; standalone items reward knowing the standard rule cold.
Core rules
- Syllogism: valid conversions are A→I ("All A are B" gives "Some B are A"), I→I, and E↔E. "Some A are B" never yields "Some A are not B".
- Circular arrangement: with n people facing the centre, the person opposite seat i is n/2 places away; when people face outward, left and right reverse.
- Blood relations: draw a tree with +/− for gender and vertical/horizontal links for child/spouse; never infer gender from a name or profession.
- Direction sense: net displacement uses Pythagoras; facing south, a left turn points you east.
- Critical reasoning: an assumption is unstated but necessary; an inference must follow from the passage alone.
Worked example
Statements: All pens are books. Some books are red. Conclusions: (I) Some pens are red. (II) Some red are books. The middle term "books" is undistributed, so no link between pens and red is forced - I does not follow. "Some books are red" converts to "Some red are books", so II follows. Answer: only II follows.
Traps
- Reading "All A are B" as "All B are A" - illicit conversion.
- Ignoring qualifiers in puzzles: "only", "immediately", "not", "between".
- Over-solving data sufficiency: sufficiency matters, the actual value does not.
- Assuming every series alternates by a constant difference; check squares, primes and ×2+1 patterns.