Logical and Abstract Reasoning
Logical and Abstract Reasoning tests pattern recognition and deductive validity, not general knowledge. You will see number or letter series, abstract shape sequences, syllogisms, and short deduction puzzles. The skill is to identify the rule that explains every term, then test the answer choices against it.
Series
- Check differences, then second differences, then ratios.
- Look for alternating sequences, squares, cubes, primes, and letter positions.
- Confirm a rule on at least three terms before applying it.
Syllogisms
- All A are B and All B are C gives All A are C.
- Some is not reversible: Some A are B does not mean Some B are A in ordinary exam logic unless the statement supports it.
- No A are B is reversible: No B are A.
- Validity is about structure, not whether the statement is factually true.
Deduction
- Convert conditional statements to their contrapositive: If P then Q means If not Q then not P.
- Do not assume the converse: If P then Q does not mean If Q then P.
- Use elimination on answer choices that add information or reverse a relation.
Worked example
All medics are first-aid trained. Some medics are drivers. Which must be true? A) All drivers are medics. B) Some first-aid trained people are drivers. C) All first-aid trained people are medics. D) No drivers are first-aid trained. The medics who are drivers are also first-aid trained, so B follows. A and C reverse the relation. D contradicts the overlap between medics and drivers.
Traps
- Assuming the converse of a conditional.
- Treating some as all or as none.
- Choosing an answer that is plausible but not forced.
- Missing a two-rule series that alternates operations.