1, rounding method: 0, 1, 2, 3, 4, none carry, 5, 6, 7, 8, 9, carry.

2. One-to-one method: One-to-one method is to add the approximate value obtained in this way to the last number of the reserved part after removing the redundant number.

3. Truncation method: Truncation method is a commonly used mathematical method, which removes the decimal part of a number and takes its integer part, and its value is approximate. This method is often used in life.

4. Quantity unit estimation method: use real-life objects to perceive the quantity unit and size of actual empirical data.

Related information:

The meaning of division is to know the product of two numbers and one of the factors and find the other factor. Division of numbers is the inverse of fractional multiplication.

Calculation rule of fractional division: A divided by B (except 0) equals the reciprocal of A multiplied by B. When the divisor is less than 1, the quotient is greater than the dividend; When the divisor equals 1, the quotient equals the dividend; When the divisor is greater than 1, the quotient is less than the dividend.

Three digits, division, hundreds of divisors, write a few if the quotient is enough, and don't cross if the quotient is not enough. One hundred digits constitute a new number, and several vendors are not bad. Business should be written in ten places, and if it is sloppy, it will fall behind. Don't blame one writer, there is more than one business. If the quotient is not enough, fill in zero and leave one digit as the remainder.