Question 1
Five boxes A, B, C, D, and E are stacked one above another (bottom to top numbered 1 to 5).
Box C is at position 3. Box A is immediately above box B. Box D is at the bottom.
Which box is at the top of the stack?
Step-by-step Solution:
1. Create position table (1 = bottom, 5 = top)
2. Direct assignments:
- Box D is at bottom → Position 1 = D
- Box C is at position 3 → Position 3 = C
3. Key constraint: Box A is immediately above Box B
- They must occupy consecutive positions: (1,2), (2,3), (3,4), or (4,5)
- Position 1 is D, Position 3 is C → only (4,5) is available
- Therefore: Position 4 = B, Position 5 = A
4. Remaining box: E goes to Position 2
5. Final stack (bottom to top):
- Position 1: D
- Position 2: E
- Position 3: C
- Position 4: B
- Position 5: A
6. Answer: Box A is at the top
Verification: All constraints satisfied ✓
1. Create position table (1 = bottom, 5 = top)
2. Direct assignments:
- Box D is at bottom → Position 1 = D
- Box C is at position 3 → Position 3 = C
3. Key constraint: Box A is immediately above Box B
- They must occupy consecutive positions: (1,2), (2,3), (3,4), or (4,5)
- Position 1 is D, Position 3 is C → only (4,5) is available
- Therefore: Position 4 = B, Position 5 = A
4. Remaining box: E goes to Position 2
5. Final stack (bottom to top):
- Position 1: D
- Position 2: E
- Position 3: C
- Position 4: B
- Position 5: A
6. Answer: Box A is at the top
Verification: All constraints satisfied ✓