Sexagesimal system
Also called: Base-60 system · Topic: Bronze Age Civilisations: Mesopotamia, Egypt, China · NCERT: Class 11, Ch 1 "Writing and City Life"
Meaning
The sexagesimal system is a way of counting based on the number 60. It is also called the base-60 system. It was invented by the Sumerians of Mesopotamia. Our 60-minute hour, 60-second minute and 360-degree circle all come from it. It shows how far Mesopotamian mathematics had advanced.
Example
Mesopotamian tablets of c. 1800 BCE contain several kinds of tables: multiplication and division tables, tables of squares and square roots, and tables of compound interest. One tablet gives the square root of 2 as 1 + 24/60 + 51/60² + 10/60³. That works out to 1.41421296, very close to the true value of 1.41421356.
Don't confuse with
- Decimal system: it counts in tens, and it is the system we use for most counting today. The sexagesimal system counts in sixties. We still use it for time and for angles.