A * * * to put 78. One side of the expressway needs 800÷20- 1=39, and both sides need 78. This is a simple arithmetic problem. The content of arithmetic includes two parts. The first part discusses the reading, writing and basic operations of natural numbers. This part includes carry system and notation, mainly decimal system.

Other decimal systems and decimal systems only adopt different cardinality, and they can all be calculated by imitating the principle and principle of decimal numbers. Another part of arithmetic includes the application of arithmetic operation methods and principles. Such as the calculation of fractions and percentages, various quantities and their calculation, ratios and proportions, and arithmetic application problems.

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Arithmetic evolution

Arithmetic is a branch of mathematics, including natural numbers, properties of various operations, operation rules and practical applications. However, in the history of mathematical development, the meaning of arithmetic is much broader.

It was not until the Song and Yuan Dynasties that the word "mathematics" appeared. In the field of mathematicians, mathematics and arithmetic are often used together. Of course, the mathematics here only refers to the mathematics in ancient China, which is different from the mathematical system in ancient Greece, and it focuses on the study of algorithms.

From19th century, some western mathematics disciplines including algebra and trigonometry were introduced into China. Western missionaries mostly used mathematics, Japanese later used the word mathematics, and China still used "arithmetic" in ancient arithmetic.

1953, chinese mathematical society established a committee to examine mathematical terms, and defined the meaning of "arithmetic", but arithmetic and mathematics still coexist. 1937, Tsinghua University also had a "computing department". 1939, in order to unify, a special "mathematics" was determined.