CHSL — General Intelligence & Reasoning: Syllogism

Practice these 20 carefully selected MCQs on Syllogism for CHSL 2026. Each question includes the correct answer and a clear explanation. Practising MCQs regularly is the best way to improve speed and accuracy.

Instructions

  • Attempt all questions without looking at answers first.
  • Time yourself: target 1 minute per question.
  • Review explanations for every wrong answer.

Q1. All cats are dogs. All dogs are horses. Conclusion: All cats are horses.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — If All A are B, and All B are C, then All A are C. Valid syllogism.

Q2. Some fruits are vegetables. All vegetables are food. Conclusion: Some fruits are food.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Some fruits → vegetables → food. So some fruits are food. TRUE.

Q3. No cow is a bird. All birds can fly. Conclusion: No cow can fly.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — Some birds can fly, and cows are not birds. But we cannot conclude no cow can fly definitively without more info.

Q4. All men are mortal. Socrates is a man. Conclusion: Socrates is mortal.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Classic syllogism: All A are B. X is A. Therefore X is B. TRUE.

Q5. Some A are B. Some B are C. Conclusion: Some A are C.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — This conclusion does NOT necessarily follow from the premises.

Q6. All roses are flowers. No flower is a tree. Conclusion: No rose is a tree.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — All roses are flowers, no flower is a tree → No rose is a tree. TRUE.

Q7. Some pens are books. All books are tables. Conclusion I: Some pens are tables. Conclusion II: All tables are books.

  • A. Only I follows
  • B. Only II follows
  • C. Both follow
  • D. Neither follows
Answer: A — Conclusion I: Some pens → books → tables. TRUE. Conclusion II: Converse of universal is not valid. FALSE.

Q8. All cups are plates. All plates are bowls. Conclusion: All cups are bowls.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Transitive: All A→B, All B→C → All A→C. TRUE.

Q9. No teacher is a student. Some students are intelligent. Conclusion: Some intelligent people are not teachers.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Some students are intelligent & no teacher is a student → some intelligent are not teachers.

Q10. All fish live in water. Shark is a fish. Conclusion: Shark lives in water.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Classic syllogism. TRUE.

Q11. Some chairs are tables. Some tables are wooden. Conclusion: Some chairs are wooden.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — 'Some' premises do not guarantee the conclusion about chairs being wooden.

Q12. All mango trees bear mangoes. This tree bears mangoes. Conclusion: This tree is a mango tree.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — Fallacy of affirming the consequent. Not all mango bearers are mango trees.

Q13. No doctor is an engineer. Ravi is a doctor. Conclusion: Ravi is not an engineer.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — No A is B. Ravi is A. → Ravi is not B. TRUE.

Q14. All politicians are liars. No liar is trustworthy. Conclusion: No politician is trustworthy.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — All A→B, No B→C → No A→C. TRUE.

Q15. Some artists are singers. Some singers are dancers. Conclusion: Some artists are dancers.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — With 'Some–Some' the conclusion is uncertain.

Q16. All computers are machines. All machines need electricity. Conclusion: All computers need electricity.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Transitive universal affirmatives. TRUE.

Q17. No rat is a cat. Some cats are bats. Conclusion: Some bats are not rats.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — No rat is a cat. Those cats that are bats are not rats. TRUE.

Q18. All rivers flow to the sea. Ganga is a river. Conclusion: Ganga flows to the sea.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Straightforward universal syllogism. TRUE.

Q19. Some tables are chairs. All chairs have legs. Conclusion: Some tables have legs.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: A — Some tables → chairs → legs. TRUE.

Q20. All heroes are brave. Some warriors are brave. Conclusion: Some warriors are heroes.

  • A. True
  • B. False
  • C. Uncertain
  • D. Cannot say
Answer: C — Sharing a predicate does not imply identity of subjects.

Exam Tips for Syllogism

  • Regular practice of 20+ questions daily builds speed and accuracy.
  • Review your mistakes — understanding why you got it wrong is crucial.
  • Attempt this topic in full mock tests under timed conditions.