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 Possible Solution by Stelian Trandafir)

Stelian Trandafir wrote: "6 keys/ person"

And then you replace each person's 6 keys with one key -- one key that unlocks everything those 6 keys collectively unlocked.

1 key/person

 

Posted by Penny on 2004-03-04 07:58:55