Detailed description:

The method of filling ten is the basic idea of carry addition within 20. By using the method of filling ten, the carry addition within 20 can be transformed into the familiar problem of 10 plus several, which makes it difficult and easy.

Ten-complement method, the simplest and most elementary rounding method, is the basis of rounding method.

Extended data:

Rounding ten: adding another number to a number to make it "ten" is called rounding ten. For example, add "2" to "8" to make it full of "10". ? Sum of ten: when calculating the sum of several numbers, first add two numbers whose sum is ten or dozens, or two or three numbers whose sum is ten, which is called sum of ten.

With the method of ten, the result can be calculated quickly. Rounding method is the basis of rounding method. Is the simplest and most elementary rounding method. ? Rounding method: when several numbers are added, first calculate the numbers that can make up whole ten, whole hundred, whole thousand and whole ten thousand. ? According to one addend, one addend increases and the other addend decreases by the same number, and their sum remains unchanged.

Turn a number close to whole ten, whole hundred, whole thousand and whole ten thousand into a number of whole ten, whole hundred, whole thousand and whole ten thousand. ? Among the fast calculation methods of addition and subtraction, rounding is the most commonly used and the best method.

Ten-point formula

Look at large numbers, divide them into decimals, make up ten, and add up the remainder. Clap your hands, children. Let's sing ten songs. ?