Reasoning Ability – Puzzles
(For the Arunachal Pradesh Forest Guard Examination)
1. Simple Explanation
Puzzles are a type of reasoning question where you have to deduce the correct arrangement, order, or relationship among a set of objects (people, objects, places, etc.) using the clues given.
They test logical thinking, attention to detail, and the ability to follow multiple constraints simultaneously.
2. Key Points to Remember
| # | What to Look For | How to Approach |
|---|---|---|
| 1 | Clues – Each clue gives a relationship (e.g., “Person A is next to Person B”, “X is older than Y”) | Read all clues once, underline the key words (next to, before, after, opposite, etc.). |
| 2 | Variables – Identify what you’re arranging (people, dates, items, positions, etc.) | List all variables in a table or diagram. |
| 3 | Structure – Decide if it’s a seating, sequence, date, ranking, or mapping puzzle. | Draw a simple grid or line, depending on the type. |
| 4 | Process of Elimination | Mark impossible options in red; keep only the feasible ones in green. |
| 5 | Cross‑Checking | After a partial solution, re‑read clues to verify consistency. |
| 6 | Time Management | Allocate 1–2 minutes for each puzzle; if stuck, move on and revisit later. |
3. Worked Example
Puzzle
**Four friends – A, B, C, and D – are standing in a straight line from left to right.
- A is standing to the right of B.
- C is standing to the left of D.
- B is not standing next to D.
- A is not standing next to C.
- D is standing in the middle position.
Question: What is the exact order from left to right?
Step‑by‑Step Solution
| Step | Action | Reasoning |
|---|---|---|
| 1 | Place D in the middle (position 3). | Clue 5 |
| 2 | Since C is left of D, C must be in position 1 or 2. | Clue 2 |
| 3 | A is right of B ⇒ A cannot be in position 1. | Clue 1 |
| 4 | B not next to D ⇒ B cannot be in position 2 or 4. | Clue 3 |
| 5 | A not next to C ⇒ if C is in position 1, A cannot be in position 2. | Clue 4 |
| 6 | Test C in position 1: | |
| > - B cannot be position 2 or 4 → only position ? (none) → contradiction. | Eliminated | |
| 7 | Place C in position 2. | Only remaining valid spot for C |
| 8 | With C at 2, B cannot be 1 or 3 (next to D). So B must be at 4. | From Step 4 and 3 |
| 9 | A must be right of B and not next to C → only left is position 1. | Clues 1 and 4 |
| 10 | Final order: A – C – D – B (left to right). | All clues satisfied |
Quick Check
| Clue | Verify |
|---|---|
| 1. A right of B | A pos 1, B pos 4 → No ❌ |
| We made a mistake – A must be right of B, but we placed A left of B. | |
| Wait, we mis‑read earlier: Actually A is right of B → B must be left of A. Let's restart quickly. |
Corrected Attempt
| Step | Action |
|---|---|
| 1 | D in middle (pos 3). |
| 2 | C left of D → C in pos 1 or 2. |
| 3 | B not next to D → B cannot be pos 2 or 4. |
| 4 | A right of B → A cannot be pos 1. |
| 5 | A not next to C → if C pos 1 → A cannot be pos 2. |
| 6 | Try C pos 1: then B cannot be pos 2 → B pos 4. A must be right of B → A pos ? (none). ❌ |
| 7 | So C pos 2. |
| 8 | B cannot be pos 1 or 3 → B pos 4. |
| 9 | A right of B → impossible. ❌ |
Hmm, still contradictory. Let's revisit: "A is standing to the right of B" means A is somewhere to the right (not necessarily immediately). So with B at 4, A cannot be right of B → impossible. So B cannot be 4. But B cannot be 2 or 4; only 1 or 3. But 3 is D. So B must be 1. Then A right of B → A can be 2,3,4. A not next to C. If C pos 2, A cannot be 1 or 3? Wait A not next to C → if C pos 2, then A cannot be pos 1 or 3. So A must be pos 4. Works! Let's finalize:
- B pos 1
- C pos 2
- D pos 3
- A pos 4
Check all clues:
- A right of B → yes (4 > 1).
- C left of D → yes (2 < 3).
- B not next to D → B pos 1, D pos 3 → not adjacent. ✅
- A not next to