After rewriting a number into a number using "ten thousand" as the unit, there is no change in the size of the number, only a change in the counting method.

Rewriting of integers: Rewrite a multi-digit number into a number using "ten thousand" or "hundred million" as the unit. When rewriting, just click the decimal point in the lower right corner of the tens of thousands or billion digit, and then put the decimal Remove the 0 at the end and write tens of thousands or billions of words. The rewritten number is an accurate number, equal to the original number, and is connected with "=". ?

Approximate number: Sometimes according to actual needs, the mantissa after a certain digit of a number is omitted to find its approximate number. Usually the "rounding" method is used to find the approximate number of a number, and the approximate number and the original number are connected with "~".

Questions about "rewriting numbers" can be roughly divided into three types: one is to rewrite the number of a whole thousand or a hundred million into a number using "ten thousand" or hundreds of millions as the unit; the second is to rewrite the number that is not a unit of "ten thousand" or a hundred million. Numbers that are in the tens of thousands or not in the hundreds of millions are rewritten into numbers using "ten thousand" or "hundred million" as the unit. The third is to use the "rounding method" to get an approximation of the number.

The importance of learning mathematics:

1. Mathematics is closely related to our lives. The real effect of learning mathematics is not reflected in exam-oriented education, but in one's own thinking in the future.

2. The importance of mathematics is self-evident. Mathematics is the foundation of all sciences and an important channel for cultivating logical thinking. It can be said that every major progress of our mankind has strong support from the subject of mathematics.

3. The application of mathematical knowledge in life is everywhere. From the calculation of the cost of firewood, rice, oil and salt in daily life, to astronomy and geography, quality control, agricultural economics, and aerospace industry, there is a shadow of the use of mathematics.