Numeration Systems

The base 60 system seems very strange to Western readers. From long habit, we are accustomed to the decimal system, and it is easy to understand numbering systems based on two (arms), five (fingers), ten (fingers on both hands), and so on. However, the base 60 system survives in our time-measuring system of 60 seconds to a minute and 60 minutes to an hour. It also survives in angle measurement and in navigational systems that measure longitude and latitude: 60 seconds equal one minute of arc, 60 minutes equal one degree of arc, and 360 degrees of arc equal an entire circle.

The base 60 system began with the Sumerians in Mesopotamia around 3000 B.C. No one knows how it got

started, though scholars speculate that it had something to do with the 60 to 1 ratio between the weights of the Sumerian measurement system. Others speculate that it was the result of the combining of a base 6 and base 10 numbering system. A rational explanation for using 60 as a base is that 60 can be divided evenly by 2, 3, 4, 5, and 6, which simplifies many computations.