[net.puzzle] the spider and fly

rainbow@ihuxe.UUCP (10/04/84)

Subject: The Geodesic Fly

Consider a box, 46 inches long, 10 inches wide, and 10 inches high.
Place a fly on one of the square ends, 5 inches from
either side and one inch from the bottom.
Similarly, place a spider on the other square ends, 5 inches from
either side and one inch from the top.
The fly (having a death wish) wants to reach the spider as soon as possible.
Find the shortest path (52 inches) between the fly and the spider.

Answer:Consider the diagonal walk down to the floor(short side), to a side
wall, up to the ceiling, to the far end, and down to the spider. Expand
box onto a flat surface and you see you've just proceeded in a straight line
between two points. By the definition, the shortest distance. The base of
the diagonal line is 48, the height 20. Trigonometry says thats 52. Of course
the fly could just take to the air. The problem should state how far does the
spider have to go for dinner.

Robert