Reasoning Ability – Puzzles
LIC ADO – Program “Reasoning Ability”
Puzzles are a popular section in competitive exams. They test your ability to apply logic, deduction, and pattern recognition to solve unfamiliar problems quickly.
1. Simple Explanation
A puzzle in reasoning is a problem that asks you to find a hidden pattern, determine the order of events/objects, or deduce relationships between items using limited information.
- Goal: Use logic, not memorised formulas.
- Process:
- Read Carefully – note every clue.
- Create a Visual Aid – tables, grids, or diagrams.
- Apply Deduction – eliminate impossibilities, infer relationships.
- Verify – ensure all clues are satisfied.
2. Key Points – What to Look For
| Category | What to Check | Why It Matters |
|---|---|---|
| Sequential Order | “First, second, last” clues | Determines placement in a line or list |
| Positional Relations | “Next to”, “between”, “two places away” | Builds a spatial map |
| Attribute Matching | “Red shirt with blue tie” | Forms a constraint matrix |
| Time/Date Sequence | “Earlier than”, “after” | Helps build a timeline |
| Exclusion Rules | “Not X”, “cannot be Y” | Narrows possibilities |
| Logical Paradox | “If A then B, but A is false” | Spot contradictions |
| Assumptions | “All husbands are married to one wife” | Avoid over‑extending a rule |
Tip: Start with the most restrictive clues (e.g., “exactly one person between X and Y”) – they give you anchor points.
3. Worked Example
Puzzle
Scenario:
In a conference, six speakers (A, B, C, D, E, F) are to present in a single row.Clues
- A speaks immediately after B.
- D speaks before E.
- C does not speak immediately before or after F.
- F is the third speaker.
- E does not speak last.
- The speaker after D is not C.
Question: What is the exact order from first to last?
Solution Steps
| Step | Action | Reasoning |
|---|---|---|
| 1 | Place F | Clue 4: F is third. |
| 2 | Use clue 1 | A is immediately after B → B‑A pair. |
| 3 | Insert pair | Since F is third, B and A must occupy positions 4 & 5 or 1 & 2. |
| 4 | Apply clue 2 | D before E. |
| 5 | Clue 5 | E not last → E cannot be 6th. |
| 6 | Clue 6 | Speaker after D is not C → C cannot be immediately after D. |
| 7 | Clue 3 | C not adjacent to F. → C cannot be 2nd or 4th. |
| 8 | Trial | Place D at 1 → then E cannot be 2 (D before E) and not 6, so E at 4 or 5. But if E at 4, then after D (1) is position 2, which cannot be C; allowed. |
| 9 | Check B‑A pair | If B at 5, A at 6 → satisfies A after B. |
| 10 | Check all constraints | Final order: D – E – F – C – B – A? Wait: C cannot be adjacent to F (C at 4 next to F at 3) → invalid. |
| 11 | Re‑try | Place D at 2 → then E at 4 or 5. If E at 5, after D (2) is position 3 (F), allowed. |
| 12 | Place B‑A pair | Must be positions 1 & 2? No, B‑A pair cannot include D at 2. So B at 1, A at 2 → but D is at 2 → conflict. |
| 13 | Try D at 4 | Then E must be after D → E at 6 (but E cannot be last). → invalid. |
| 14 | Try D at 5 | Then E after D impossible. → invalid. |
| 15 | Try D at 1 | Re‑evaluate: D at 1, E at 4 or 5. C cannot be 2 or 4. Let's set E at 5. Then positions: 1-D, 2-?, 3-F, 4-?, 5-E, 6-?. |
| 16 | Place B‑A | The only remaining slots for B‑A pair are 2‑4 (adjacent). If B at 2, A at 4. Check: C cannot be adjacent to F → C cannot be 4 or 2. C must be 6. |
| 17 | Check all clues | 1. A(4) after B(2) – yes. 2. D(1) before E(5) – yes. 3. C(6) not adjacent to F(3) – yes. 4. F(3) third – yes. 5. E(5) not last – yes. 6. After D(1) is F(3) – not C – yes. |
Final Order:
| Position | Speaker |
|---|---|
| 1 | D |
| 2 | B |
| 3 | F |
| 4 | A |
| 5 | E |
| 6 | C |
4. Quick Revision Summary
| Topic | Quick Check |
|---|---|
| Read every clue |