This trick will surely amaze your friends (well at least some of them).
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Based on the reviews, some folks like the app and some folks hate it....
hahahahaha AMAZING!! by Giovanisf13 - Version 1.1.0 - Feb 24, 2009 - 5 Stars
I dont know how it works but its AWESOME !!!! THE BEST MAGICIAN APP IN THE APP STORE. I really recommend it. Now i know the trick but it keeps 5 stars:) -Giovanisf13.com
Stupid by Mathwizard19283 - Version 1.1.0 - Mar 5, 2009 - 1 Star
For all you who dont get it, it works like this: You have a number xy xy = 10x+y xy-y = 10x 10x-x = 9x making it a multiple of 9 xy-(x+y) = 9x, and all multiples of nine have the same symbol
Well... it doesnt really matter if you love it or hate it... its just a trick, and if done right can be a cool trick to show your friends.
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You tell your audience to pick a number between 10 and 99 (lets say 23 in this example).
Then they add those two digits together(2+3=5)
Then they subtract that number from their original number (23-5=18).
Then they look up that number on the symbols chart, and they memorize the symbol that corresponds with the number (18).
Finally, they will click on the crystal ball, and the symbol that they memorized will mysteriously appear.
NOTE FROM DEVELOPER: Yes, you will eventually figure out how the trick works. The fun in doing a magic trick is not in knowing how its done, but in being able to impress your friends with the trick.
The trick will work equally well with one person, as it will in an auditorium full of people.
Special attribution is being given to Andy Naughton for his previous work on a similar adaptation of this math trick. His original work can be seen on flashlightcreative.com. http://www.flashlightcreative.co.uk/flashlight/index.php?option=com_content&view=article&id=38:mindreader&catid=1:flash&Itemid=4