1, which is probably widely used in daily life. Prediction is a kind of ability to roughly estimate the operation process and results. In real life, many things are actually impossible and do not need accurate calculation. A scholar once made a statistic and compared the probability of accurate calculation and rough calculation in daily life, and found that the latter was much more. For example, if our family wants to plan income and expenditure, it needs to be estimated; What is the turnover and profit of a shopping mall? We have to make a rough forecast, which is also an estimate: for example, there are a lot of floating population in big cities now, so we should also make some estimates when making statistics. It can be seen that estimation is indispensable in life. Therefore, it is reasonable to put forward estimation as a new content in mathematics teaching.

2. Estimation provides a basis for judging whether the results of calculator, oral calculation and written calculation are reasonable. Estimation provides an important basis for judging whether the calculator is accurate, including whether the results of children's oral calculation and written calculation are reasonable. Pupils begin to use calculators, and the calculation results are generally accurate, but sometimes there are problems due to operational errors. If students have the awareness and ability to estimate, they can quickly find out whether the results calculated by the calculator are reasonable or not. In the past, we used the reciprocal relationship of addition and subtraction and the reciprocal relationship of multiplication and division to check, but now we can use estimation to solve it, which is also an important application of estimation.

3. Estimation helps people to grasp the range of operation results in advance, which is an important way to develop students' sense of numbers.

4. Estimation plays an important role in students' subsequent mathematics learning.