How to cut a cake fairly into N pieces

Suppose you have N people and one cake. How can you cut the cake such that each person is satisfied that the pieces have been distributed fairly? This is an old problem that Martin Gardner wrote up in his column for Scientific American and in the case of two people it is quite simple: One person gets to cut the cake into two and the other person gets to select the piece they want. (But see later for a problem with this.)

But what if there are more than two people? Below the fold, I give Gardner’s explanation on how to do it, starting with the case where N=3, quoted by Walter Stromquist in an issue of The American Mathematical Monthly.
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The next president of the Philippines?

Later today, the Philippines will officially declare the winner of its presidential elections. There are five candidates running and since there is no run-off, the winner needs only a plurality to become president. I had not been aware until today that the candidate currently leading in the vote count and expected to win, Rodrigo Duterte, has a horrific record and platform and has made no secret for his disdain for democratic checks and balances if they stand in the way of his agenda.
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This is the way to deal with frightened passengers

By now pretty much everyone must have heard about the academic who was taken off a plane and questioned by authorities because the passenger seated next to him while the plane was waiting to be cleared for takeoff had alerted the authorities that he was behaving suspiciously, concentrating on writing strange symbols on a piece of paper and rebuffing her attempts at conversation as she tried to find out what he was up to. It did not help that he was youngish, swarthy looking, and bearded.
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When numbers are outlawed, only outlaws will have numbers

Via Mark Frauenfelder, I came across this fascinating little video that informs me that being in possession of a particular number is now illegal in the US and why. I cannot tell you the full number because I don’t know it but apparently knowing it and even writing it on a piece of paper could land me in prison. All I know is that the number is a prime number that has 1419 digits that begin with the sequence 85650789657397829.
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