A Cool Penny Trick

This little trick with pennies is a good gag to play with friends or family.  Basically you bet someone that you can correctly predict a number by pulling that exact number of pennies from your pocket. To set up the trick you have to cut a penny in half.  Then pull 4 full pennies and one of your 1/2 pennies out of your pocket and put them in your hand.  Tell the person you are betting against, that you will correctly choose the exact number of pennies based off of the number they pick.  Then tell them to choose any 2 digit number.  Then have them split up the digits and add them together (ie. if they picked 27, they would add 2+7, if they pick 76, then 7+6, etc.). Then they need to subtract the total of this addition problem from their original number (ie. 27 - (2+7) = 27 - 9 = 18, 76 - (7 +6) = 76 - 13 = 63, etc.).  Then they need to add the two digits of the result together (ie. 1 + 8 = 9, 6 + 3 = 9, etc.).  then they need to divide that result by 2.  They will get 4 1/2 every time.  Be sure to emphasize that you have the exact number of pennies in your hand as their result.  They'll think they've won, since there's "no way" you can have 1/2 a penny in your hand.  Then reveal your 4 1/2 pennies and laugh all the way to victory!