We're all pretty familiar with the Arabic numeral system, dating back to 873 CE. They're the symbols we use to represent numbers today across the world, whether we're telling time (It's 12:00 pm) or counting money ($4.99, please) or ranking sports teams (The Bears are #1). Arabic numerals are everywhere!
There are, however, other numeral systems, dating much further back in history, one of the most interesting being Maya numerals. The Maya civilization spanned 125,000 square miles of Mesoamerica, with a rich history stretching back as far as 2000 BCE. Part of what makes their culture so fascinating is their numeral system, which uses base 20 instead of base 10. The chart below shows the symbols the Maya used. Can you find the pattern?
The pattern uses a larger oval for 0, a dot for 1, and a bar for 5. Then, once the number reaches 20, we add on a new group of symbols above the first group, to indicate how many groups of 20 we have.
(Fun fact: in the Gettysburg Address, when President Lincoln said "four score and seven years ago," he was using a similar pattern. One score represents 20 of something. Can you identify how many years President Lincoln counted in his speech?)
Here's a diagram demonstrating how to write numbers larger than 20 in Maya numerals.
Can you write how old you are in Maya numerals? How about how many inches tall you are? Maya numerals can be tricky, but they're fascinating to work with.