Suppose some lions and lambs satisfy:
- There are at least two lions.
- Each lion has bitten at least three lambs.
- For any two lions, there is exactly one lamb that has been bitten by both.
- For any two lambs, there is at least one lion that has bitten both.
- One of the lions has bitten six lambs.
How many lions are there? How many lambs are there?
Source: Andy Liu, Univ. of Alberta
© Copyright 2001 Stan Wagon. Reproduced with