A group of five people want to put a set of locks on a chest and distribute keys to the locks amongst themselves in such a way that all the locks on the chest could be opened only when at least three of them were present to open it.

How many locks would be needed, and how many keys?

(In reply to Revised solution to revised puzzle by Penny)

Why not use your original solution (comment #6) and just have a separate key for each lock: 10 locks and 30 keys?

Posted by Charlie on 2004-03-04 12:04:18