LANCE BURTON'S SECRETS OF MAGIC:
"ODD OR EVEN"
The magician asks an audience member to momentarily turn around, take some coins from his pocket, and hold them inside a closed fist. The magician removes some coins from his pocket, and holding them in his closed fist, turns and says, "We both have coins concealed in our hands. Although I have absolutely no idea how many coins you have hidden in your hand, I can positively predict that when my coins are added to yours, if your amount is odd... it will become even. If however, your amount is even, then it will change to odd.
The audience member counts his change and finds that he has an odd number of coins. The magician adds his coins to the spectator's and, as predicted, the total changes to even.
SECRET: Although it would appear that the solution to this swindle depends on the magician's ability to secretly ascertain the exact amount of coins concealed in the audience member's hand, nothing could be further from the truth. The trick works regardless of the amount. The secret lies in the fact that the magician's hand always contains an odd amount of coins. The odd amount of coins, when added to the audience member's will make an even amount total odd, and an odd total even.
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