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As a country strong in maths, China has many folk games filled with maths wisdom. You may have played many of them before. Let's take a look at three of them.
Lu Ban lock
Lu Ban lock was first created by Chinese carpenter Lu Ban about 2,000 years ago. It is said that Lu used six wooden pieces to make a toy that looks like a lock for his son. The lock has a lot to do with solid geometry (立体几何). It's hard to separate the six pieces. However, it is usually easier to unlock a Lu Ban lock than to put it back together. Now, there are Lu Ban locks made up of nine or more pieces.
Huarong pass
Huarong pass is a traditional Chinese block - moving puzzle. Every block is named after a character in the book *Romance of the Three Kingdoms*, like Cao Cao, Zhang Fei and Zhao Yun. To succeed in the game, players have to move the blocks to get "Cao Cao" out. This is a test of one's maths knowledge, for example, of geometric area (几何面积). According to the Chinese Puzzle website, it takes at least 81 steps to set "Cao Cao" free.
Chinese nine linked rings puzzle
An early record of this type of puzzle can be found in *Strategies of the Warring States* (《战国策》) from the Western Han dynasty. The nine linked rings puzzle, also called the Chinese ring puzzle, is usually made up of nine rings connected to a handle. Players have to remove all the rings from the handle to win the game. This is not a simple game. The solution takes 341 moves, so you need to be very patient. For example, if you want to remove the ninth ring, you have to remove the third, fifth, and seventh ones first. If you start from the eighth, you won't be able to do it.