Blog posts with problems to get your brain going! You get a new problem every fortnight and the solutions are published later.

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The next problem is scheduled for Sunday, 2nd of May.

You may notice some problems are missing... I'm still migrating articles from my old blog.


Alice and Bob sit down, face to face, with a chessboard in front of them. They are going to play a little game, but this game only has a single knight... Who will win?


Some people are standing quiet in a line, each person with a hat that has one of two colours. How many people can guess their colour correctly?

Alice and Bob are going to be locked away separately and their faith depends on their guessing random coin tosses!


I find the problem in this post rather fun to think about because it is a problem about a game that can actually be played between two players.