Monty Hall Problem

One day I was showed this problem and I really couldn't wrap my head around it. In the end, it took me several hours to understand the logic and believe it is true.

Anyways, the video explaining Monty Hall Problem is here:

And here is a real life proof that it works:

And a video of folk dance if this mathematical thing gets too much:

In the video you can also see how the folk dance club works: first, everyone are trying to remember how the dance went. Then one brave couple starts to do some kind of moves and others join in quickly.

Have fun! ;)