Skip to 0 minutes and 0 seconds[music] In the previous video we learned about the Mayan number system, which has the characteristic of functioning in base 20 instead of base 10, like our decimal system does. Now it's time to apply the number system with arithmetic. Let's learn how to do addition. For example, 85+123. Now let's write these quantities in the Mayan number system and arrange them in a matrix. We know the result of this addition is 208, and the technique to apply addition within the matrix is very simple. You just put together the symbols contained in the cells in each row, rewrite if necessary and see if you are not exceeding the last Mayan number system symbol available, which in this example we are not.

Skip to 0 minutes and 55 secondsLet's see another case, for example 15+5. We know that the result will be 20 but how will this work within our matrix? Let's write the Mayan number symbols for each quantity. Now put them together in one cell. In this example, we exceed the last Mayan number system symbol available. So we need to using rewrite the next digit position. Now it's time to analyze substraction. Let's do 101-2, which we know the result is 99. But on the matrix something very interesting is going to happen. The key to solve this subtraction is by breaking the Mayan number system symbols whenever it's necessary. The 5'th Mayan symbol on the 2'nd row which is a line, can be broken into 5 dots.

Skip to 1 minute and 46 secondsAt the same time, one of the dots can be broken into 4 lines but in the 1st cell of the 1st row. Now let's break one of those lines into 5 dots. Next, we just eliminate the same amount of dots for both cells in the 1st row and finally move the remaining symbols to the result column. Now, let's learn multiplication. For example, 28 x 2. We know the result is 56. In this case, we need to write 2 times the symbols contained in each of the cells. But, you still have to rewrite correctly when necessary. Finally, we're going to see an example of division. For instance, 40 divided by 5, which we know the result is 8.

Skip to 2 minutes and 35 secondsIn this case, we have to break the symbol contained in the 1st cell of the 2nd row and pair it with the 2nd cell of the 1st row. Now we have to find how many times does the line symbol appear? which we already know is 8. So far, we have seen the basics of the Mayan number system and its arithmetic. We encourage you to practice by doing other examples and read more about this amazing meso-american culture.

# Mayan arithmetic

Thanks - Erika and Eric Roldan, for sharing this with us. If you have any questions about Mayan arithmetic, please post in the discussions!

© Erika and Eric Roldan, Mexico