Two series of reading methods: first read ten thousand levels, then read four levels; Ten thousand numbers should be read according to the pronunciation of the first level, and then a word of one ten thousand should be added at the back; No matter how many zeros are at the end of each level, neither read nor read; Other numbers have one or several zeros in succession, all of which are read-only 1 zeros.
Reading rules:
Pronunciation of numbers within 1 and 1 100 million
(1) No matter how many zeros there are at the end of a number, don't read it. Such as: 5632 10000, 4856000000.
(2) Don't read the "0" at the end of each level. Such as: 20005830, 60058402300
(3) Other numbers have "0". No matter whether there is one "0" or several "0" in succession, only one "0" is read. Such as: 50064058, 600442085009.
2. The new situation in the reading of 100 million series-all the ten thousand grades are "0"
Such as: 4850000 1768
When we know the number within 100 million, it is impossible to "all levels are 0". In this case, this "0" does not belong to the end of a number, the "0" at the end of each level, or the "0" in the middle of each level. This is the only new knowledge in the billion series of reading methods. There is no need to supplement it in the textbook. Tell the students that all levels are "0" and only one "zero" is read.
3. Summary: Read a zero rule.
Except for the two cases of "the end of a number or the end of each level", other numbers have a "0" or consecutive "0" s all read only a zero.
As long as you remember that the zeros at the end of a number or at the end of each level are not read, then other numbers, no matter how many zeros there are, read only one zero, which is easy to understand and remember.
Counting from right to left (refers to the integer part), every four digits are one level.
Class 100,000
100,000,000,000,000.
Billion billion billion billion
The 0 at the end of each stage is not read.
204700 can be divided into 20 parts? 4,700 readings: 204,700
Extended data:
We call all nonnegative integers such as 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, … natural numbers. Forward extension of 1, 2, 3, …, 9, 10 gives a positive integer 1, 2, 3, …, 9, 10, … backward extension gives a negative integer …
"0" between a positive integer and a negative integer is a neutral number; Put them together to get …,-1 1,-10, -9, …, -3, -2,-1, 0, 1, 2, 3, …, 9,655.
Integer can perform four operations: addition, subtraction, multiplication and division, which are called four operations. Integer, addition, subtraction, multiplication and division operations form a closed set of numbers, which is the research object of the ancient branch of mathematics "number theory"
The famous German mathematician Gauss said: "Mathematics is the queen of science, and number theory is the crown in mathematics". Division operations, such as 7/ 1 1 = 0.636363 …,1/7 =1.5714285 …, are no longer integers, that is to say, integers are not equal to division operations.
In order to close the number set of four operations of addition, subtraction, multiplication and division, new numbers need to be added, such as 7/ 1 1/7, which is the ratio of two integers, called comparable numbers and fractions, and is now commonly known as rational numbers.
Summarize and sort out the nature of numbers and the experience of four operations between numbers in the application process, and form the oldest mathematics-arithmetic. The set of rational numbers, the four operations of addition, subtraction, multiplication and division form a closed set of numbers, which looks very complete. More than 2500 years ago, many people, even some mathematicians at that time, thought so.
References:
Mathematics _ Baidu Encyclopedia