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, 7th of March.

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

Five sailors and their monkey were washed ashore on a desert island. They decide to go get coconuts that they pile up. During the night, each of the sailors, suspicious the others wouldn't behave fairly, went to the pile of coconuts take their fair share. How many coconuts were there in the beginning..?


\(n\) mathematicians with numbered party hats gather around in a circle... It is a matter of life or death!


Is it true that every integer you can think of has a multiple written out only with \(0\)s and \(1\)s?

In this post I talked about the riddle of the water buckets. Now I challenge you to prove that in some situations it is impossible to solve it!