Math guys, how does this thing work?
 

How does this darn thing keep getting it right?

http://www.regiftable.com/regiftingrobinpopup.html

Hasn't gotten one right yet......

First, the grid is set up so that any number you pick will give you the same gift. For insance, if box 9 has Keychain, 10-0-0=9 and 11-1-1=9 and 12-1-2=9 etc, so they all give you the keychain.

Then it rearranges the grid each time, so you get a new gift if you try again. You think that because you picked a different number you got a different gift, but it's really just because the gifts are in different boxes. Most people will be too amazed to notice that the gifts are in different boxes.

It has nothing to do with math.

Your number ends up being a multiple of 9....9-18-27-36 and they are all the same thing but change every time like Graham says.

nevermind

The 'puter watches where you put your mouse pointer. Natural tendency is to point to the gift you are looking at. it remembers and shows you that gift on the next page.

gtc is most correct.

Look at 40 up to 49, then 50, 51, 52, etc.

40 - 4 - 0=36

41 - 4 - 1=36

42 - 4 - 2=36

43 - 4 - 3=36

44 - 4 - 4=36

45 - 4 - 5= 36

46 - 4 - 6=36

47 - 4 - 7=36

48 - 4 - 8=36

49 - 4 - 9=36

You could pick 50, 51, 52...

50 - 5 - 0=45

51 - 5 - 1=45

52 - 5 - 2=45

etc.

Thus, there are certain values, {9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99} that are going to be the result when you pick ANY number. These are all multiples of 9.

Notice how every one of these numbers {9, 18, 27, 36, 45, 54, 63, 72, 81, 90, 99} is the same thing. It is the only gift you are going to imagine. Thus, it just has to show you whatever is in these boxes. And, like Graham says, they change what's in the "multiples of 9" box every time..

Reminds me of a joke that works the same way....

Pick any number between 1 and 10.

Multiply that number by 9.

Sum the digits of the answer (i.e. 5x9=45, 4+5=9)

Subtract 5 from your sum.

The remaining number corresponds to a letter in the alphabet (i.e. 1=A, 2=B, etc..)

Think of a country whose name begins with that letter.

Think of the second letter in the name of that country.

Think of an animal that begins with that letter.

Think of the color of that animal.




















Wait for it

































What makes you think that there are gray elephants in Denmark?

The operational premise is that you do in fact know arithmetic.