Subject: Crossing the river with dogs
Date: Tue 2/2/99 11:04 AM
From: Patti Sprague
I found a logic puzzle in an old file left by a previous teacher, but no solution to the puzzle. It goes something like this: Five owners must cross a river with their respective dogs. There is one boat which will hold three living things, people or dogs or a combination thereof. All the owners know how to drive the boat, and one extremely intelligent dog can also drive. All 10 must get across the river, but no dog can be left (even momentarily) with another owner unless his own owner is present. Dogs may be left with dogs. Owners may be left with owners. How can the crossing be accomplished, and how many trips are necessary?
Girard Middle School