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Case 28: who took the Antique Violin?
During last night's private gala at the theater, a guest must have gotten a little too close to the Antique Violin, on display in the Props Room, because it was gone by morning. The guest list is short; so is the room for error. Help the police unmask the thief.
The board
- 1Storage Room
- 2Makeup Room
- 3Props Room
- 4Dressing Room
- 5Costume Room
- 6Office
- 7Stage
- 8Orchestra Pit
- 9Café
- Seat: anyone can be on it.
- Table: nothing can be on its cell.
- Screen: nothing can be on its cell.
- Window: the blue line on a wall.
Suspects and clues
- NNoah
He's in column F. - CChidi
He's 4 columns away from the Props Room and in row 7. - SSandra
She's in the Storage Room. - FFarah
She's next to a window. - EElena
She's next to a screen. - MMatthew
He's 2 rows away from the Café. - HHana
She's right next to the Stage. - AAntique Violin (stolen item)
It's in a corner, and it's not in the Office.
Remember the rules: no two suspects (nor the item) ever share a row or a column, each character is in a different room, and the thief is the only one sharing a room with the stolen item. Unsure? Read how to play and the clue types.
Solution
Try it yourself first: pen and paper are enough. When you want to check, open the reasoned solution.
Show the step-by-step solution
- Noah's clue: He's in column F. 6 cells remain possible: F3, F4, F5, F6, F7 and F8.
- Chidi's clue: He's 4 columns away from the Props Room and in row 7. It leaves a single cell: B7.
- Sandra's clue: She's in the Storage Room. 7 cells remain possible.
- Farah's clue: She's next to a window. 6 cells remain possible: G1, H2, A3, D3, A6 and H7.
- Elena's clue: She's next to a screen. 2 cells remain possible: B1 and C2.
- Matthew's clue: He's 2 rows away from the Café. It leaves a single cell: H5.
- Hana's clue: She's right next to the Stage. 19 cells remain possible.
- The stolen item's clue: It's in a corner, and it's not in the Office. 31 cells remain possible.
- Chidi can only be on B7. No one else can be in row 7 or column B, and no other character can be in the Stage.
- B1 has already been ruled out, so Elena can only be on C2. No one else can be in row 2 or column C, and no other character can be in the Orchestra Pit.
- Matthew can only be on H5. No one else can be in row 5 or column H, and no other character can be in the Office.
- C4, B5, C5, D5, B6 and C6 have already been ruled out, so Sandra can only be on A6. No one else can be in row 6 or column A, and no other character can be in the Storage Room.
- Every other cell the clue allowed has already been ruled out, so Hana can only be on E8. No one else can be in row 8 or column E, and no other character can be in the Props Room.
- Every cell still open to Noah is in column F, so no one else can be in that column.
- Proof by contradiction. Suppose Farah were on D3. Following the rules above, the Antique Violin would be left with no possible cell. So Farah is not on D3.
- H2, A3, D3, A6 and H7 have already been ruled out, so Farah can only be on G1. No one else can be in row 1 or column G, and no other character can be in the Dressing Room.
- The item must share its room with one character: the thief. No character can be in the Makeup Room any more, so the Antique Violin isn't there either.
- Every other cell the clue allowed has already been ruled out, so the Antique Violin can only be on D4. No one else can be in row 4 or column D.
- F4, F5, F6, F7 and F8 have already been ruled out, so Noah can only be on F3.
Conclusion: Noah is the only person sharing the Costume Room with the Antique Violin, which is on D4. He is the thief.