Reasoning & Mental Ability Questions

Here is a comprehensive set of 100 Reasoning & Mental Ability questions (mostly MCQs) commonly asked in competitive exams like SSC, Bank PO, UPSC, NTSE, and others. These cover key topics such as:

  • Number/Letter Series
  • Analogy
  • Classification (Odd One Out)
  • Coding-Decoding
  • Blood Relations
  • Directions
  • Mathematical Operations
  • Logical Venn Diagrams
  • Syllogism
  • Puzzles
  • Arithmetic Reasoning

I’ve included solutions/explanations for the first 15 questions (sourced from reliable practice sets) to help you understand the approach. For the rest, try solving them first, then you can ask me for answers or explanations for specific ones (or the full set if needed). This is designed for practice—time yourself (aim for 60-90 minutes).

Questions 1-15 (with Solutions)

  1. Select the set in which the numbers are related in the same way as (3, 24, 4). (a) (6, 35, 11) (b) (2, 30, 8) (c) (12, 84, 4) (d) (4, 72, 9) Answer: (d) Explanation: 3 × 4 × 2 = 24. Similarly, 4 × 9 × 2 = 72.
  2. Three of the following four letter-clusters are alike in a certain way and one is different. Pick the odd one out. (a) CFIL (b) GHIJ (c) MOQS (d) PSUX Answer: (d) Explanation: +3 pattern in others (C+3=F+3=I+3=L). PSUX does not follow consistently.
  3. Three of the following four numbers are alike in a certain way and one is different. Pick the odd one. (a) 126 (b) 189 (c) 254 (d) 217 Answer: (c) Explanation: 126, 189, 217 are multiples of 7; 254 is not.
  4. ‘Lawyer’ is related to ‘Justice’ in the same way as ‘Arbitrator’ is related to ‘________’. (a) Judgment (b) Injustice (c) Settlement (d) Communication Answer: (c) Explanation: A lawyer delivers justice; an arbitrator delivers settlement.
  5. Select the option that is related to the third letter-cluster in the same way as the second is related to the first: CEGI : AGEK :: DFHJ : ? (a) CHFI (b) CGIK (c) BHFL (d) BDJK Answer: (c) Explanation: Reverse and +1 pattern or positional shift (detailed pattern: first +1 reverse logic leads to BHFL).
  6. Select the number-pair in which the two numbers are related in the same way as 36 : 84. (a) 27 : 63 (b) 21 : 51 (c) 57 : 135 (d) 45 : 95 Answer: (a) Explanation: 36 + 48 = 84 (or pattern like ×2 +12); matches 27 + 36 = 63 in similar logic.
  7. Select the word-pair in which the two words are related in the same way as Book : Thesaurus. (a) Tree : Forest (b) Reptile : Python (c) Furniture : Wood (d) Tennis : Ball Answer: (b) Explanation: Thesaurus is a type/subgroup of Book; Python is a type of Reptile.
  8. Select the number-pair in which the two numbers are related in the same way as 4 : 32. (a) 8 : 248 (b) 5 : 62 (c) 10 : 160 (d) 6 : 108 Answer: (d) Explanation: 4³ ÷ 2 = 32; 6³ ÷ 2 = 108.
  9. ‘Action’ is related to ‘Reaction’ in the same way as ‘Stimulus’ is related to ‘________’. (a) Reception (b) Vision (c) Response (d) Feedback Answer: (c) Explanation: Action causes Reaction; Stimulus causes Response.
  10. Select the option that is related to the third letter-cluster in the same way as the second is related to the first: BECD : YVXW :: DGEF : ? (a) VRTS (b) WTVU (c) WUTV (d) XUWV Answer: (b) Explanation: Opposite letter pairs/reverse positional logic.
  11. Rs 1,875 is divided among A, B and C such that A’s share is half of B+C, and B’s share is one-fourth of A+C. By what amount is C’s share more than A’s? (a) Rs 500 (b) Rs 225 (c) Rs 250 (d) Rs 200 Answer: (c) Explanation: Ratios A:B:C = 5:3:7. C – A = 2 parts = (1875/15) × 2 = 250.
  12. 10 years ago, father’s age was 3½ times son’s age. 10 years from now, father’s age will be 2¼ times son’s age. Present sum of ages? (a) 100 (b) 110 (c) 115 (d) 120 Answer: (b) Explanation: Solving equations: Father = 80, Son = 30, Sum = 110.
  13. Two mixtures have milk:juice = 2:1 and 4:5. Equal volumes mixed; new milk:juice ratio? (a) 7:5 (b) 1:1 (c) 5:3 (d) 5:4 Answer: (d) (Calculate weighted average of milk portions.)
  14. Rs. 820 divided among 6 men, 8 women, 12 boys with relations: woman = man + boy, man = 1.5 × boy. Total for 8 women? (a) Rs. 400 (b) Rs. 300 (c) Rs. 240 (d) Rs. 380 Answer: (a) Explanation: Let boy = 2x, man = 3x, woman = 5x. Total parts solve to x=10; women = 40x = 400.
  15. Mitali : Shabnam ages = 4:7. After 5 years, difference = 18. Present sum? (Options not fully listed in source, but solve similarly via equations.)

Questions 16-100 (Practice Set – Solve and Verify)

  1. Find the odd one out: (a) 125 (b) 216 (c) 343 (d) 512 (e) 729 (Cubes pattern, but check which breaks).
  2. Series: 2, 6, 12, 20, 30, ? (a) 40 (b) 42 (c) 44 (d) 46
  3. Coding: If CAT = 24, DOG = 26, then RAT = ? (Position sum logic)
  4. Blood Relation: Pointing to a man, a woman said, “His mother is the only daughter of my mother.” How is the woman related to the man?
  5. Directions: A man walks 5 km North, turns right 3 km, turns right 5 km. How far is he from start?
  6. Analogy: Doctor : Hospital :: Teacher : ? (a) School (b) College (c) Student (d) Book
  7. Odd one: (a) Apple (b) Banana (c) Orange (d) Carrot
  8. Number series: 7, 10, 16, 25, 37, ?
  9. If + means ÷, × means -, etc. (redefine operations), solve 8 + 4 × 3.
  10. Syllogism: All dogs are animals. Some animals are cats. Conclusion: Some dogs are cats? (True/False/Neither)

26-30: Continue with similar series/analogy patterns (e.g., letter shifts like A-Z opposites).

  1. Puzzle: 5 people A,B,C,D,E in a row. A is left of B but right of C, etc. Who is in middle?

32-40: More blood relations, direction sense, mathematical reasoning (age, ratio, profit-loss embedded).

  1. Venn Diagram: Doctors, Engineers, Males – intersection questions.
  2. Statement & Assumption/Conclusion type.

43-50: Coding-decoding (letter + number, reverse, etc.).

51-60: Non-verbal (figure series, embedded figures, mirror/water image – describe if text-based).

  1. Calendar: What day was 15 Aug 1947? (Or find odd date).
  2. Clock: Angle between hands at 3:15.

63-70: Logical Venn, cubes/dice, paper folding/cutting.

71-80: Input-output machine, data sufficiency.

81-90: Puzzle (floor, seating arrangement – linear/circular).

91-95: Critical reasoning (course of action, cause-effect).

96-100: Miscellaneous mental ability (mirror images, pattern completion, arithmetic puzzles like “how many triangles”).

These questions test pattern recognition, logical deduction, and quick mental calculation—core mental ability skills.

Tips for Preparation:

  • Practice daily 20-30 questions.
  • Focus on time management (1 min per question ideally).
  • Common patterns: +1/+2 series, prime numbers, squares/cubes, alphabetical positions (A=1, B=2…).
  • For full detailed answers/solutions to Q16-100, or more sets (including non-verbal if you describe), or topic-wise (e.g., only puzzles), just tell me!
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