The diagram above represents the layout of a new prison.
There are 21 guards, 45 prisoners, 6 towers for the guards, and 5 compounds for the prisoners.
The towers are numbered 1 to 6 and the compounds are lettered A to E.
All of the compounds are triangular in shape and have a guard tower at each of the three corners.
The number of prisoners in a compound is equal to the total number of guards in the towers on the corners of the compound.
There are 11 prisoners in compound A, 1 guard in tower number two, and 3 guards in tower number six.
No two towers or compounds contain the same number of guards or prisoners.
How many guards are there in each of the six towers?
Solution to the Problem:
There are 1, 2, 3, 4, 5, and 6 guards in the six towers.
James Alarie found two solutions to the problem -- the one above and the following:
Correctly solved by:
| 1. Ivy Joseph | Pune, Maharashtra, India |
| 2. Rob Miles | Northbrook, Illinois |
| 3. James Alarie ** | Flint, Michigan |
| 4. Garima Mandwani | Pune, Maharashtra, India |
| 5. Don Norris | Watkinsville, Georgia |
** Extra credit for finding two solutions