Division with remainder

Division with remainder is as follows:

Division with remainder is also called divisor algorithm.

First of all, we need to understand how the remainder in division is produced. When we studied division last semester, we used the concept of average score. The total score can always be divided into several parts according to the number of each part.

Now, if the total number is not divisible, that is, it is not divisible, and the remaining number is not divisible and less than the number of each part, this is the remainder, that is, the remainder must be less than the divisor, otherwise it can continue to be divisible and the quotient will increase.

For example, 25 peaches are evenly divided into four plates. After six plates are divided, there is one peach left, but there is still some left after the division. This remainder is less than 4, which is not enough to divide a plate, so a remainder is generated.

Secondly, we say that division is the inverse of multiplication, while division with remainder is actually the inverse of multiplication and addition. The inverse operation of 25 ÷ 4 = 6 ... 1 is 6×4+ 1=25. Therefore, on the basis of the original quantitative relationship of division, we need to know the new quantitative relationship of quotient × divisor+remainder = dividend.

Because there is a remainder, we can't directly use the multiplication formula to find the quotient as we did last semester. You have to try the business first. If the product is greater than the dividend, the quotient is large. If the remainder is greater than the divisor, the quotient is smaller.

One big and one small means that the right quotient is sandwiched between these two numbers. This is the so-called "double-sided" thinking method, so for children, you can't get the result directly, so you have to try.

Thirdly, vertical division is a difficult point, which is very different from the previous vertical addition and subtraction: instead of writing the operation symbol directly, it is replaced by a symbol similar to the prefix "factory". In addition to vertical calculation, there are subtraction calculations. Pay attention to the digit alignment of quotient and dividend. The writing quality here is very important.