Students, what I want to explain to you today is the understanding of 100. This knowledge point is one of the foundations for us to learn mathematics. It can help us better understand the concept of number and lay a solid foundation for future study.

First of all, we need to know what is a number within 100. Simply put, those numbers are between 1 and 100. In this range, there are integers, decimals and negative numbers. Integers may be familiar to you, such as 1, 2, 3, 4. Decimals are those numbers with decimal points, such as 1.5, 2.7, etc. Negative numbers are numbers like-1 and -2.

Next, we will learn how to read these numbers. For example, the number 35 is pronounced as 35. For decimals, we also read the whole part and then add the decimal point. For example, 1.5 is pronounced as 1.5. For negative numbers, we also read them by adding a negative sign to the integer part. For example,-1 is pronounced as negative one.

Next, we will learn how to write these numbers. For integers, we can write them directly in Arabic numerals. For example, 35 can be written as 35. For decimals, we also write decimal points and decimal parts directly. For example, 1.5 can be written as 1.5. For negative numbers, we also add a negative sign to the integer part. For example,-1 can be written as-1.

Finally, let's learn how to compare these figures. In fact, the method of comparison is also very simple, that is, look at the positions of these numbers on the number axis. The number axis is a straight line extending infinitely from left to right, and we can put all the numbers on this straight line. For example, two numbers, 20 and 35, we can find their positions on the number axis and compare their sizes. Because 20 is to the left of 35, 20 is less than 35.

This is what we learned today. I hope it will help you. In the learning process, everyone should actively think and practice, and firmly grasp every knowledge point.