**Fido claims that he can read our mind.**

**Click at the following link to test him out!!! :**

**http://www.digicc.com/fido/**

**There are several ways to explain Fido's trick, u**

**sing mathematical reasoning.**

*Make an attempt to use ALGEBRA to explain the "trick"?*
Enter your thinking (algorithm) in Comments.

*up to 10 points to be awarded to the most complete answer that's explained in a simple to understand way*
What I think:

ReplyDeleteThere are only 9 digits since he said don't pick 0. I believe that all 3 and 4 digit numbers when their digits are jumbled up and subtracted, their answers are always different, so it is possible to guess the number missing using the other 3/2/1 number(s).

I tried putting 123 as the number and changed the way the numbers were placed, and each time i got 3. This means that the number given is not random, and is based on the input. That also means that no matter what, as long as 1, 2, and 3 together is the input, 3 is the answer.

1, 2, 3, and 3 can make many answers for even more starting numbers.

(I am not sure if this counts as algebra, this is just how I would explain)