Lösung noch nachliefere:
8 Zimmer - 8 Schlüssel = 8x
7 Zimmer - 7 Schlüssel = 7x
6 Zimmer - 6 Schlüssel = 6x
5 Zimmer - 5 Schlüssel = 5x
4 Zimmer - 4 Schlüssel = 4x
3 Zimmer - 3 Schlüssel = 3x
2 Zimmer - 2 Schlüssel = 2x
1 Zimmer - 1 Schlüssel = 1x
ergibt zusammen........= 36 mal