Rounding: 0, 1, 2, 3, 4, no carry, 5, 6, 7, 8, 9, carry. Become law? One method is to add the approximate value obtained in this way to the last number of the retained part after removing the redundant number, which is the redundant approximate value (that is, greater than the accurate value).

The importance of mathematics to children's growth;

Exercise the way of thinking. Primary school mathematics can train students' thinking mode and improve their thinking and understanding ability. Cultivate study habits. Primary school mathematics teachers play an active role in cultivating students' comprehensive ability, so that students can make greater progress.

Improve the efficiency of life. Elementary school mathematics can teach students some basic knowledge, such as: addition, subtraction, multiplication and division, area calculation, volume calculation and so on. To make students more relaxed in real life.

Improve innovation ability:

Mathematics learning can help children cultivate their innovative ability, because there is often more than one solution to mathematics problems, and children need to keep trying to innovate to solve them. In the process of solving mathematical problems, children need to be creative and flexible, and create their own problem-solving methods through divergent thinking and innovative thinking.

Improve comprehensive quality:

Math learning can also help children improve their overall quality. Mathematics learning not only needs to be attentive and meticulous, but also needs children to have high self-study ability, time management ability and cooperation ability.

Because mathematics learning needs unremitting struggle and study, and also needs appropriate pressure, children need to learn to adjust their learning rhythm and mentality in order to develop in other aspects of their educational career.

Cultivate logical thinking ability;

Mathematics is a rigorous discipline, which emphasizes solving problems with accurate logical thinking. In the process of mathematics learning, children need to constantly improve their logical thinking ability, be good at analyzing problems, find laws and summarize methods.

These abilities can not only improve students' performance in mathematics, but also help them solve various practical problems more easily. Because logical thinking is a key to children's success, it can help children better understand and deal with the surrounding information.