In the previous blog, we looked at how the numbers we use in mathematics were formed using the **decimal number system**. In this system, we use multipliers of ten to define the positions for the number’s digits. There are other number systems that used multipliers of twenties instead of tens. This **vigesimal number system** was used by the Pre-Columbian **Mayan civilization** as their way of representing quantities.

The Mayans used the following three unique symbols to represent numbers: A seashell symbol which is used to represent **zero**, a dot used to represent **one** unit, and a stroke used to represent **five** units. They used these symbols to represent the numbers 0-19 as follows:

The Mayans wrote their numbers vertically. The bottom slot in any number has a multiplier of 1. The next slots above them increase by multiples of 20, as shown in the diagram below. They Mayans defined numbers by placing one or more of the twenty **digits** from above in the appropriate slots. Note that the Mayans used zero as a placeholder just like the Indians did in the Hindu-Arabic Number System (See “India & Zero” blog).

Lets use this information to decipher a mayan number (**A**).

We translate the symbol into a hindu-arabic number and we multiply it by the multiplier associated with its vertical position (**B**). We add the values of each position and come up with the value of the Mayan number (**C**). In this example, the Mayan number (**A**) has a value of 96,410.

There are only three undisputably authentic Maya codices in existence today. The only one of these three to contain mathematical symbols is the one referred to as the **Dresden Codex**. It is currently at the Saxon State Library (Sächsische Landesbibliothek) of Dresden, Germany. A high-quality high-resolution image of the codex is available at this website for you to explore. See examples of how the Mayans wrote down numbers and see if you can decipher them using what you learned in this blog.