C and was used by the Egyptians. "The word calculus means stone, so did the word calculate." a Many people used stones to the same object, in America, the Peruvian Incas used knotted strings, for their accounts and they called him quipos. With the passage of time Portable invented the abacus which consisted of a plastic beads on a string as their time were fixed in a wooden stand. Today in our time are these abacus, but the balls are set on wood supports or wires. a With the discovery of the abacus could work in the ancient world and with some business agility, which made use of this nifty tool to make their calculations and mathematical operations. Use of the abacus a spread throughout Europe until the Middle Ages, but when the Arabs implanted the decimal numbering system using the abacus began to decline. a In the use of the abacus in our times there is an anecdote.
946, which is very important to state, in that year there was a competition of speed of calculation between an American and a Japanese, American used a calculator and Japanese used an abacus, the competition was won by the Japanese. a 1. 2 DECIMAL NUMBERING SYSTEM. a At the time of the conquest of Darius and the expeditions of Alexander, which put India in touch with the civilizations of the Near East and Greece. Indian mathematicians already knew the use of Babylonian numbering system for position. Hindus adapted to decimal numbers, and created and position the decimal system, which we know today.