how is this done ?

[Su]

this is an old magicians' trick I know ..

but how is it done ?

<a href='http://www.mot.be/dutch/GuessTool.htm' target='_blank'>http://www.mot.be/dutch/GuessTool.htm</a>

 

[mark]

Clever stuff indeed........

no matter what number you choose ther are only 10 possible answers - every number in the 90,s = 81, every number in the 80's = 72 every number in the 70's = 63 etc etc, so the 10 results will always be - 81, 72, 63, 54, 45, 36, 27, 18 and 9 - and for these the picture is the same - they want you to refresh all the time as each time you refresh the image on the 9 possibles changes

Cheers

 

[Su]

There were a couple of tricks I knew as a kid involving the #9

blow me down if I can remember them now