Eight boxes - J, K, L, M, N, O, P and Q are arranged one above the other in a stack, but not necessarily in the same order
Only L is kept above J.
At most one box is kept below box P.
| | Case 1 | Case 2 |
| Sr. no | Boxes | Boxes |
| 1 | L | L |
| 2 | J | J |
| 3 | | |
| 4 | | |
| 5 | | |
| 6 | | |
| 7 | | P |
| 8 | P | |
Q is kept immediate above N.
Three boxes are kept between N and O.
| | Case 1 | Case 2 |
| Sr. no | Boxes | Boxes |
| 1 | L | L |
| 2 | J | J |
| 3 | O | Q |
| 4 | | N |
| 5 | | |
| 6 | Q | |
| 7 | N | P |
| 8 | P | O |
Neither N nor O is kept immediately below J.
Thus, case 1 is invalid.
Box K is kept below box M.
Therefore, the final arrangement is:
| Sr. no | Boxes |
| 1 | L |
| 2 | J |
| 3 | Q |
| 4 | N |
| 5 | M |
| 6 | K |
| 7 | P |
| 8 | O |
If all boxes are arranged in alphabetical order from topmost to bottommost positions in the stack, then we get:
| Sr. no | Boxes | Alphabetical order |
| 1 | L | J |
| 2 | J | K |
| 3 | Q | L |
| 4 | N | M |
| 5 | M | N |
| 6 | K | O |
| 7 | P | P |
| 8 | O | Q |
So, the position of only one box remains unchanged.
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