This is not right. The purpose of teaching children to estimate is to let students know the estimation method and "material" in the process of solving practical problems in life, and express the estimation results with "material". For example, in life, buy electrical appliances: a TV set is 3987 yuan, and a refrigerator is 2286 yuan. How much does it cost to buy these two things? What we are asking here is about. Our children, who are only in the second grade, are not required to master the addition and subtraction of four digits, but only to calculate how much they need through estimation. In the process of estimation, we generally teach them to use rounding method, which can estimate to hundreds, that is, it takes about 6220 to estimate 3987 to 3900, 2286 to 2300, 3900+2300=6200. This is a method, or simply estimate to thousands. It is estimated that 3987 is 4000, and 2286 is 2000,4000+2000 = 6000.
When we talk about estimation, we usually regard a number as a whole ten, a whole hundred or a whole thousand. If the estimate is the same as the actual number, it is not an estimate, but a calculation.