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Case 2: who took the Mother-of-Pearl Shell?
Amid the chaos of a school visit at the aquarium, someone took advantage of the confusion to make off with the Mother-of-Pearl Shell, on display in the Office. For once, the suspect list doesn't include any nine-year-olds. Help the police unmask the thief.
The board
- 1Restrooms
- 2Café
- 3Terrace
- 4Office
- 5Tank Room
- Table: nothing can be on its cell.
- Screen: nothing can be on its cell.
- Window: the blue line on a wall.
Suspects and clues
- CChidi
He's in column E. - NNadia
She's next to a table. - AAmara
She's in row 1, and she's not in the Restrooms. - GGrace
She's 1 row away from the Office and 2 rows away from the Café. - HHugo
He's in the Office. - MMother-of-Pearl Shell (stolen item)
It's 1 column away from the Café.
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
- Chidi's clue: He's in column E. 6 cells remain possible: E1, E2, E3, E4, E5 and E6.
- Nadia's clue: She's next to a table. 3 cells remain possible: B4, A5 and B6.
- Amara's clue: She's in row 1, and she's not in the Restrooms. 3 cells remain possible: A1, B1 and E1.
- Grace's clue: She's 1 row away from the Office and 2 rows away from the Café. It leaves a single cell: D6.
- Hugo's clue: He's in the Office. 3 cells remain possible: C5, D5 and C6.
- The stolen item's clue: It's 1 column away from the Café. 5 cells remain possible: F1, F2, E3, B4 and E4.
- Grace can only be on D6. No one else can be in row 6 or column D, and no other character can be in the Tank Room.
- D5 and C6 have already been ruled out, so Hugo can only be on C5. No one else can be in row 5 or column C, and no other character can be in the Office.
- A5 and B6 have already been ruled out, so Nadia can only be on B4. No one else can be in row 4 or column B, and no other character can be in the Terrace.
- There are as many suspects (counting the item) as columns, so each column holds exactly one. Only Amara can still reach column A, so that is where she must be.
- B1 and E1 have already been ruled out, so Amara can only be on A1. No one else can be in row 1 or column A, and no other character can be in the Café.
- E1, E2, E4, E5 and E6 have already been ruled out, so Chidi can only be on E3. No one else can be in row 3 or column E, and no other character can be in the Restrooms.
- F1, E3, B4 and E4 have already been ruled out, so the Mother-of-Pearl Shell can only be on F2.
Conclusion: Chidi is the only person sharing the Restrooms with the Mother-of-Pearl Shell, which is on F2. He is the thief.