The meaning of decimals and their reading and writing methods

Decimals consist of integer parts, decimal parts and decimal points. When measuring an object, it is often not an integer, so the ancients invented decimals to supplement integer decimals, which is a special form of fractional fractions. Fractions with denominators of 10, 100, 1000 ... can be expressed in decimals. All fractions can be expressed as decimals, except infinite acyclic decimals, all decimals can express the number of components. Irrational numbers are infinitely cyclic decimals. According to the decimal bit value principle, the decimal part is written in the form without denominator, which is called decimal. The point in the decimal is called the decimal point, which is the dividing line between the integer part and the decimal part of a decimal. The part to the left of the decimal point is an integer part, and the part to the right of the decimal point is a decimal part. Decimals with zero integer parts are called pure decimals, and decimals with non-zero integer parts are called decimals. For example, 0.3 is pure decimal, 3. 1.

To understand the meaning of decimals, we can start with the meaning of fractions, which can be explained by subdivision and comprehensive activities. When a whole (reference quantity) is divided into equal parts, the quantity in which some parts gather is called "component", and this "component" is expressed or recorded by "fraction". For example, 2/5 refers to the "component" in which an integer is divided into five equal parts and then aggregated into two halves. When the whole is divided into 10, 100, 1000, etc. Use another method to record the weight at this time-decimal. For example,110 is 0. 1, 2/ 100 is 0.02, 5/ 1000 is 0.005 and so on. The "."is called the decimal point, which is used to separate the integer part from the decimal part that cannot form an integer. Integers that are not 0 are called decimals, and those that are 0 are called pure decimals. So the meaning of decimals is part of the meaning of fractions.

There are two ways to read decimals: one is to read fractions, and the whole part with decimals is to read integers; The fractional part is read by the fraction. For example, 0.38 is pronounced as 38%, and 14.56 is pronounced as 14 and 56%. In another way, the integer part is still read as an integer, the decimal point is read as a "dot", and the decimal part reads the numbers on each digit in sequence. For example, 0.45 is read as 0.45; 56.032 is pronounced as 56.032.