BigRiddles
The circular lake (alternative answer...)
posted by Taketa - January 23 2011 10:45:41 AM
A swan sits at the center of a perfectly circular lake. At an edge of the lake stands a ravenous monster waiting to devour the swan. The monster can not enter the water, but it will run around the circumference of the lake to try to catch the swan as soon as it reaches the shore. The monster moves at 4 times the speed of the swan, and it will always move in the direction along the shore that brings it closer to the swan the quickest. Both the swan and the the monster can change directions in an instant.

The swan knows that if it can reach the lake's shore without the monster right on top of it, it can instantly escape into the surrounding forest.

How can the swan succesfully escape?
Reply by TannerG - February 26 2011 09:00:44 PM
http://www.bigriddles.com/riddle/the-circular-lake

Oh wait, Alertnative answer?

To post a response, simply log in with your Google Account.