CAT — Logical Reasoning (LR): Advanced Notes + 50 Practice MCQs (rsetu.link)

Why LR matters & What CAT tests

Logical Reasoning assesses structured thinking, deduction speed, and the ability to manage constraints. Key LR types: linear and circular seating, ordering and grouping, puzzles with multi-attributes, blood relations, syllogisms (Venn logic), and inference puzzles. Accuracy + systematic diagramming = high scores.

Frameworks & Diagramming Techniques

Always diagram: convert text into visuals — grids for attributes, circles or arrows for relations, table for multi-attribute puzzles.
Mark constraints: definite facts first, then conditional statements. Use shorthand symbols for repeated terms.
Use elimination: for MCQs, often easier to test options against diagram than re-derive from scratch.
Timeboxing: spend 3–6 minutes on a medium puzzle; skip & return if stuck.
Backsolve: plug options into the constraints when direct deduction is long.

Common LR Types & Quick tips

Seating (linear/circular): mark fixed positions, use L/R notation, and remember mirror symmetry for circular unless direction given.
Puzzles: create an attribute matrix. Fill definite cells first, use crosses for impossibilities.
Blood relations: translate phrases to family tree: 'X is the brother of Y' => sibling link; track genders when given.
Syllogisms: use Venn circles and standardized forms (A: All S are P; E: No S are P; I: Some S are P; O: Some S are not P).

Worked micro-examples

Seating (circular) example: A, B, C, D sit around a table. A sits opposite C. B sits to the left of A. Who sits to the right of C? Diagram quickly — answer: B.

Blood relation example: 'P is the son of Q. R is the father of Q.' => R is P's grandfather. Visual: R → Q → P.

Syllogism example: All X are Y. Some Y are Z. Conclusion: Some X may be Z (cannot be certain). Use Venn to check validity.

50 Practice MCQs — Logical Reasoning (Answers highlighted)

Practice set includes puzzles, seating, blood relations, syllogisms and quick inference MCQs. Answers are highlighted.

Q1. (Seating - circular) Six people A,B,C,D,E,F sit in a circle facing center. A sits to the immediate left of B. C sits opposite A. Who sits opposite B?

A. C

B. D

C. E

D. F

Q2. (Blood relations) 'X is the brother of Y. Y is the mother of Z.' What is X to Z?

A. Father

B. Uncle

C. Maternal uncle

D. Grandfather

Q3. (Syllogism) All M are N. No N are O. Which follows?

A. No M are O

B. Some M are O

C. All O are M

D. None

Q4. (Puzzle) Four people P,Q,R,S have different ages. P is older than Q but younger than R. S is the youngest. Who is the oldest?

A. P

B. Q

C. R

D. S

Q5. (Linear seating) Five friends sit in a row facing north. A is to the right of B. C sits at one end. If A is second from left, who is in center?

A. A

B. B

C. C

D. Cannot determine

Q6. (Syllogism) Some A are B. All B are C. Which is true?

A. Some A are C

B. All A are C

C. No A are C

D. None

Q7. (Blood relations) 'A's father is B. B's mother is C. How is C related to A?'

A. Grandmother

B. Grandmother

C. Aunt

D. Mother

Q8. (Puzzle — attributes) Three boxes X,Y,Z contain red, blue, green balls counts 5,7,9 respectively. If one ball removed from Z to X, which has most balls?

A. X

B. Z still has most

C. Y

D. All equal

Q9. (Seating - circular) If in a circular seating A opposite D and B right of A, who is left of D?

A. B

B. B

C. C

D. Cannot say

Q10. (Syllogism) All P are Q. Some Q are R. Can we conclude some P are R?

A. No, not necessarily

B. Yes

C. Only if R subset of Q

D. None

Q11. (Blood) 'X is mother of Y. Y is sister of Z.' How is X related to Z?

A. Mother

B. Aunt

C. Sister

D. Grandmother

Q12. (Puzzle) A>B, CA. Which is largest?

A. B

B. C

C. D

D. A

Q13. (Seating) In a row of 6 facing south, who is to left of person facing north? Trick question.

A. None — all face south

B. Right

C. Opposite

D. Cannot determine

Q14. (Syllogism) No X are Y. Some Z are X. Which follows?

A. Some Z are not Y

B. All Z are Y

C. No Z are Y

D. None

Q15. (Blood) 'A is brother of B. C is son of B.' What is A's relation to C?

A. Uncle

B. Father

C. Brother

D. Grandfather

Q16. (Puzzle - attributes) Six students have different heights. If A taller than B,C; B taller than D; E taller than all. Who is shortest?

A. C

B. D

C. B

D. A

Q17. (Seating) For circular arrangements, mirror images are equivalent unless direction specified. True or False?

A. True

B. False

C. Only for even numbers

D. None

Q18. (Syllogism) All K are L. All L are M. Then:

A. All K are M

B. No K are M

C. Some M are K

D. None

Q19. (Blood) 'X is sister of Y. Y has a daughter Z.' X is what to Z?

A. Aunt

B. Mother

C. Grandmother

D. Sister

Q20. (Puzzle) If a>b>c and x

A. a+z > b+y

B. Cannot determine

C. a+z < b+y

D. a+z = b+y

Q21. (Seating) In linear seating facing north, left/right orientation matches viewer's left/right. True or False?

A. True

B. False

C. Only for odd numbers

D. Cannot say

Q22. (Syllogism) Some R are S. Some S are T. Can we conclude some R are T?

A. No, not necessarily

B. Yes

C. Only if sets overlap

D. Always

Q23. (Blood) 'A is father of B. C is sister of A. How is C related to B?'

A. Aunt

B. Sister

C. Mother

D. Niece

Q24. (Puzzle) If person with blue hat sits opposite person with green hat in a 6-person circle, they are separated by how many seats?

A. 2

B. 1

C. 3

D. 4

Q25. (Syllogism) No A are B. Some C are B. Which is valid?

A. Some C are not A

B. All C are A

C. No C are A

D. Cannot say

Q26. (Blood) If D is parent of E and E is sibling of F, D is _____ of F.

A. Parent

B. Sibling

C. Child

D. Cousin

Q27. (Puzzle) You have statements: (1) If it rains, ground is wet. (2) Ground is wet. Can you conclude it rained?

A. No — affirming the consequent

B. Yes

C. Only if no other cause

D. None

Q28. (Seating) In circular seating facing center, person left of A is right of whom?

A. Person right of A

B. Person opposite A

C. Person left of A

D. None

Q29. (Syllogism) All D are E. No E are F. Some F are G. Which follows?

A. No direct relation between D and G

B. Some D are G

C. All G are D

D. None

Q30. (Blood) Statement: 'P is son of Q. Q is wife of R.' How is R related to P?

A. Father

B. Mother

C. Uncle

D. Grandfather

Q31. (Puzzle) If three statements are mutually exclusive, at most how many can be true simultaneously?

A. 1

B. 2

C. 3

D. 0

Q32. (Seating) If A sits opposite B and C opposite D in a 4-person circle, who sits to the left of A?

A. D

B. B

C. C

D. None

Q33. (Syllogism) Some H are J. No J are K. Which is certain?

A. Some H are not K

B. All H are K

C. No H are K

D. None

Q34. (Blood) If M is brother of N and N is mother of O, relation between M and O?

A. Maternal uncle

B. Father

C. Brother

D. Grandfather

Q35. (Puzzle) If conditionals: (1) If A then B. (2) If not B then C. Which contrapositive is valid?

A. If not B then not A

B. If B then not A

C. If C then B

D. None

Q36. (Seating) For 8 people around table, opposite seats differ by how many positions?

A. 4

B. 3

C. 2

D. 5

Q37. (Syllogism) All S are T. Some T are U. Which is valid?

A. Some S may be U

B. All S are U

C. No S are U

D. None

Q38. (Blood) 'A is father of B. B is father of C. C is sister of D.' Relation of A to D?

A. Grandfather

B. Uncle

C. Brother

D. Father

Q39. (Puzzle) Statements: 'Either P or Q is true. Q is false.' What follows?

A. P is true

B. Cannot say

C. Both true

D. None

Q40. (Seating) For linear facing south, right of X is which direction relative to viewer?

A. Left

B. Right

C. Opposite

D. None

Q41. (Syllogism) Some V are W. No W are X. Which is certain?

A. Some V are not X

B. All V are X

C. None

D. No V are X

Q42. (Blood) 'Y is sister of Z. Z is daughter of W.' Y is _____ of W.

A. Daughter

B. Mother

C. Sister

D. Aunt

Q43. (Puzzle) Contradiction detection: Which pair contradicts: 'All cats are animals'?

A. Some cats are not animals

B. All animals are cats

C. Some animals are cats

D. None

Q44. (Seating) If 7 people sit around table, how many distinct circular arrangements (considering rotations identical)?

A. 6! (720)

B. 7!

C. 5!

D. 8!

Q45. (Syllogism) All A are B. Some B are C. Some A are C — true/false?

A. True — some A could be C (possible but not certain)

B. False

C. Always true

D. None

Q46. (Blood) If A marries B and B is sibling of C, relation of A to C is:

A. Brother/Sister-in-law

B. Child

C. Parent

D. None

Q47. (Puzzle) If statements A→B and B→C, what can you infer about A and C?

A. A→C (transitive)

B. C→A

C. Cannot infer

D. None

Q48. (Seating) In circular seating with odd number, opposite seat concept is undefined. True/False?

A. True

B. False

C. Only if 1 person odd

D. Cannot say

Q49. (Syllogism) No P are Q. Some R are Q. Which follows?

A. Some R may not be P

B. All R are P

C. No R are P

D. None

Q50. (General) Best practice when stuck on LR MCQ is:

A. Draw a minimal diagram and test options

B. Guess randomly

C. Skip without marking

D. Spend unlimited time

Practice & Test-day Tips

Practice diagramming under time pressure — make symbol shorthand for recurring constructs.
For seating, try both clockwise and counterclockwise placements quickly to test symmetry.
For blood relations, draw small family trees; mark genders if given.
For syllogisms, practice with Venn diagrams for certainty checks.
Review mistakes by pattern: misread constraint, incomplete diagram, wrong assumption.