Puzzle 133 - Double your money!

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A magician standing next to a bridge offers to double the money to a man each time he crosses the bridge. But he also charges 40$ for crossing the bridge. The man happily agrees and keeps crossing the bridge again and again. 

But sadly after the third time he crossed the bridge, the man notices that he has only 40$ left in his pocket which he has to give to the magician. How much money did the man have originally?


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