1. Approximation refers to a number that is close to the exact number, that is, a number that is not much different from the original data by rounding, entering one or truncation. An exact number refers to a number that can represent the actual number of original objects or events. This number is called accurate number.
When a divisor is rounded, it is said that it is accurate. Rounding is usually to get a value that is easier to report and communicate than the original value. Rounding is also important to avoid inaccurate calculation, measurement or estimation in the report.
3. The mixed operation of the divisor can be calculated step by step according to the operation order and the calculation rules of the divisor, but the result of the intermediate operation is one bit more than the final result. Jane is one of the most common and flexible math problems in primary schools, which can fully exercise the flexibility of students' thinking and play a very important role in improving students' computing ability.
Mathematical terms of approximation:
1, a number close to an exact number, is called a divisor. If one of the similar numbers is rounded, then the approximate number is accurate to which place, from the first one on the left that is not 0 to all the numbers that stop at the exact number. For example, the population of our country cannot be accurately calculated, but a rough figure can be given. For example, the population of our country is 65.438+0.3 billion.
2. Use rounding method to express. Where the number is rounded off, it is said that the approximate number is accurate to which place.
3. There are two other methods: entering one and ending. Represented by significant figures. There is a rounding approximation, counting from the first non-zero on the left to the last number. All numbers are called significant numbers of this number.