👉 Archelaus, also known as Archelos, is a Greek mathematician who lived in the 7th century BC. He is credited with developing the concept of the "archaic" or the "ancient" fraction system, which was later adopted by ancient civilizations such as the Babylonians and Egyptians. The term "archelaus" comes from the Greek word "arche-", meaning "to measure," and "lamos," meaning "fraction." In this context, "arch