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Thank you for subscribing! Now we're in touch: I'll write to you when the site gets new puzzles, new ways to explain them or a write-up of an interesting discussion. For me personally, it is a great honour and a real motivation to keep this project going.

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The Monty Hall problemYou're on a game show and pick one of three doors. The host, who knows where the car is, opens another door to reveal a goat and offers a switch. Should you take it?Try it → The duckweed lake puzzleDuckweed doubles every day, and one plant covers a lake in 30 days. How long do two plants take?Try it → The birthday paradoxHow many people must be in a room before two of them probably share a birthday?Try it →