1, in the formula without brackets, if there is only addition and subtraction, it should be calculated from left to right. If there are parentheses in the formula, count the inside of the parentheses first, and then the outside of the parentheses.
2. The operational nature of integer subtraction is also applicable to decimal subtraction. The key of decimal mixed operation is to master the order of operation. Calculate from left to right in turn, just like the addition and subtraction of integers. If there are brackets, count them first.
Related knowledge of decimal addition and subtraction mixed operation
1, decimal addition and subtraction mixed operation is a kind of mathematical operation that we often encounter in our daily life and study. It involves the addition and subtraction of decimals and the mixed use of these two operations.
2. First of all, let's understand the basic concept of decimal. Decimals are a way of expressing fractions. It is a digital system based on 10. For example, one tenth can be expressed as 0. 1, one percent can be expressed as 0.0 1, and so on. The number to the left of the decimal point indicates the integer part and the number to the right indicates the decimal part.
Next, let's learn the addition and subtraction of decimals. Decimal addition and subtraction are similar to the familiar integer addition and subtraction, but it should be noted that we need to align the decimal point for calculation. For example, 2.3+ 1.5=3.8 instead of 2.3+ 15= 17.3.
Similarly, when we do subtraction, we also need to align the decimal points, and then do subtraction bit by bit from right to left. For example, 4.7-2.3=2.4 instead of 47-23=24. Finally, we will discuss the addition and subtraction of decimals. In this operation, we need to do the operation in brackets first, then multiply and divide, and finally add and subtract.
This is because in mathematics, we follow the principle of "multiply first, then divide, then add and subtract". In addition, we also need to pay attention to maintaining the accuracy and consistency of the operation. Such as (2.3+1.5) × 0.4 =1.68 instead of (23+ 15)×0.4= 16.8.
6. In the actual calculation process, we also need to pay attention to some decimal precision issues. Due to the limitation of computer storage accuracy, sometimes the results we get may have some minor errors. Therefore, when we add and subtract mixed decimals, we need to keep as many significant figures as possible to improve the accuracy of the results.