Note: In the calculation results, the 0 at the end of the decimal part should be removed to simplify the decimal; When the number of decimal places is not enough, use 0 to occupy the place. Counting from the decimal point to the right, except that there is no first 0 followed by 0, the size of the decimal remains the same.
Decimal division calculation rule: first move the decimal point of the divisor to make it an integer, then move the decimal point of the divisor to the right by several digits (if the digits are not enough, make up "0"), and then calculate according to the division rule that the divisor is an integer.
Decimals are another expression of fractions. All fractions can be expressed as decimals, and the points in decimals are called decimal points, which are the dividing lines between the integer part and the decimal part of a decimal.
Extended data:
A simplest fraction can be converted into a decimal finite fraction if and only if its denominator contains only prime factors 2 or 5 or both. Similarly, a simplest fraction can be transformed into a finite fraction of the base of a positive integer if and only if the prime factor of its denominator is a subset of the prime factor of the base.
All fractions can be expressed as decimals, and the points in decimals are called decimal points, which are the dividing lines between the integer part and the decimal part of a decimal. Decimals with zero integer parts are called pure decimals, and decimals with non-zero integer parts are called decimals.
In fact, China was the first country to use decimals. As early as the 3rd century, when solving a math problem, Liu Hui, an ancient mathematician in China, suggested that the part that cannot be named below the integer digits should be called decimal. The name of decimal system was put forward by Zhu Shijie, a mathematician in China in the 3rd century/kloc-0. In the west, decimals appeared very late, until16th century, when French mathematician kravis first used decimal points as symbols to distinguish integer parts from decimal parts.
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