Monster Move Problem

Three five-handed extra-terrestrial monsters were holding three crystal globes. Because of the quantum mechanical peculiarities of their neighborhood, both monsters and globes come in exactly three sizes with no others permitted: small, medium and large. The small monster was holding the large globe, the medium-sized monster was holding the small globe, and the large monster was holding the medium-sized globe. since this situation offended their keenly developed sense of symmetry, they proceeded to transfer globes from one monster to another so that each monster would have a globe proportionate to its own size. Monster etiquette complicated the solution of the problem since it requires that: Only one globe may be transferred at a time; If a monster is holding two globes, only the larger of the two may be transferred; and A globe may not be transferred to a monster holding a larger globe. By what sequence of transfers could the monsters have solved this problem? [Hint condition: Your first goal should be to take care of the small monster (i.e., to get him the right-sized globe.)]

Monster Change Problem

Three five-handed extra-terrestrial monsters were holding three crystal globes. Because of the quantum mechanical peculiarities of their neighborhood, both monsters and globes come in exactly three sizes with no others permitted: small, medium and large. The small monster was holding the large globe, the medium-sized monster was holding the small globe, and the large monster was holding the medium-sized globe. since this situation offended their keenly developed sense of symmetry, they proceeded to shrink and expand the globes so that each monster would have a globe proportionate to its own size. Monster etiquette complicated the solution of the problem since it requires that: Only one globe may be changed at a time; If two globes have the same size, only the globe held by the larger monster may be changed; and A globe may not be changed to the same size as a globe of a larger monster. By what sequence of changes could the monsters have solved this problem? [Hint condition: Your first goal should be to take care of the small monster (i.e., to get his globe to the right size.)]

Acrobat Problem

Three circus acrobats developed an amazing routine in which they jumped to and from each other's shoulders to form human towers. The routine was quite spectacular because it was performed atop three very tall flag poles. It was made even more impressive because the acrobats were very different in size: the large acrobat weighed 700 pounds; the medium acrobat, weighed 200 pounds; and the small acrobat, a mere 40 pounds. These differences forced them to follow these safety rules: Only one acrobat may jump at a time. Whenever two acrobats are on the same flagpole, one must be standing on the shoulders of another. An acrobat may not jump if someone is standing on his shoulders. A bigger acrobat may not stand on the shoulders of the smaller acrobat At the beginning of their act the medium acrobat was on the left, the large acrobat in the middle and the small acrobat was on the right. At the end of the act, they were arranged small, medium, and large from left to right. How did they manage to do this while obeying the safety rules?

Problem Solving and Planning