I have a bag containing the digits 0 through 9, and used six of them to stick two different three-digit perfect squares on the foreheads of Paul and George. Both Paul and George know this fact, but each one can see only the other's number.

I ask Paul, "How many of the digits remaining in my bag can you exactly tell me?"

Paul replies, "Three."

If I now ask the same question to George, what should he reply?

This problem is made much easier by constructing a list  of 3DSs. This leads 2 a uniq sol by logic  (as it shud). But isnt it kewl (n dnt prtent u all kno this already) that ab©÷=cdb while ¡îbdc=ba! (no factorials intended) for specific values. Both the numbers and the functns r palllindromic (in my world at least).Free Key!. No doubt the subject of much perplection.

Posted by Percy on 2005-08-18 23:46:45