Roboku
Español
Case 9: who took the Giant Pearl?
Amid the chaos of a school visit at the aquarium, someone took advantage of the confusion to make off with the Giant Pearl, on display in the Main Aquarium. For once, the suspect list doesn't include any nine-year-olds. Help the police unmask the thief.
The board
- 1Café
- 2Office
- 3Main Aquarium
- 4Tank Room
- 5Storage Room
- 6Terrace
- 7Diving Room
- Seat: anyone can be on it.
- Shelf: no character can stand on its cell, but the stolen item can be there.
- Table: nothing can be on its cell.
- Screen: nothing can be on its cell.
Suspects and clues
- HHugo
He's in row 5. - KKenji
He's 2 columns away from the Office. - EEsteban
He's not next to any wall. - CChidi
He's in the Tank Room. - SSandra
She's 3 rows away from the Main Aquarium. - GGiant Pearl (stolen item)
It's not in the Tank Room, and it's right next to the Terrace.
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
- Hugo's clue: He's in row 5. 5 cells remain possible: B5, C5, D5, E5 and F5.
- Kenji's clue: He's 2 columns away from the Office. 2 cells remain possible: C4 and C5.
- Esteban's clue: He's not next to any wall. 4 cells remain possible: D2, B3, E4 and E5.
- Chidi's clue: He's in the Tank Room. 2 cells remain possible: F1 and F2.
- Sandra's clue: She's 3 rows away from the Main Aquarium. It leaves a single cell: A6.
- The stolen item's clue: It's not in the Tank Room, and it's right next to the Terrace. It leaves a single cell: E3.
- Sandra can only be on A6.
- The Giant Pearl can only be on E3. No one else can be in row 3 or column E.
- B3, E4 and E5 have already been ruled out, so Esteban can only be on D2. No one else can be in row 2 or column D, and no other character can be in the Diving Room.
- F2 has already been ruled out, so Chidi can only be on F1. No one else can be in row 1 or column F, and no other character can be in the Tank Room.
- There are as many suspects (counting the item) as rows, so each row holds exactly one. Only Kenji can still reach row 4, so that is where he must be.
- C5 has already been ruled out, so Kenji can only be on C4. No one else can be in row 4 or column C, and no other character can be in the Café.
- C5, D5, E5 and F5 have already been ruled out, so Hugo can only be on B5.
Conclusion: Kenji is the only person sharing the Café with the Giant Pearl, which is on E3. He is the thief.