Addition and subtraction by a column are rarely difficult even for elementary school students. However, when it comes to adults, in many cases they become so accustomed to using technology that they forget even something so simple. This is even taking into account the fact that addition and subtraction are carried out by a column in grade 2. In any case, this article will help you remember everything. It is also useful for those who need to explain the material about addition and subtraction in a column to children. However, it is even easier for children.
Mathematical "skeleton" of a number
Before learning how to do addition and subtraction examples in a column, make sure you remember the material presented in this picture using the example of the number 80783023.
Visual explanation of the principle of column addition
Carefully study how the example 157 + 358=515 was solved.
As you can see, column addition is carried out alternatelyfirst with units of numbers, then with their tens, hundreds, thousands, and so on. Let's take a closer look at what is shown in the picture.
At the first stage, the units of the numbers 157 and 358 are added. Accordingly, you need to add 7 and 8, which will equal 15. remember dozens. At the second stage, tens are added, and for these numbers, the tens are the numbers 5 and 5. The result of their addition will be 10. "So, you need to write 0 under the addition line," that's what many make a mistake. In fact, to this number you need to add the unit that remains from the number 15. This is so because for the number 15 1 is its ten, like the class of numbers whose addition process is happening right now. Thus, under the addition line, you need to write the number 1. Again, you need to remember the number 1, since it is the tenth of the resulting number 11. And in the third stage, after adding 1 and 3, you get 4, and the same unit is added to this amount, forming the number of hundreds 5. Thus, you can add any natural numbers. As for subtraction by a column, addition, in fact, is the reverse process of it. Therefore, it is executed in the same way.
Examples for addition and subtraction in a column (Grade 2)
Try the following column addition problems:
- 374 + 91=
- 4862 + 57834=
- 1784 + 467=
You can check yourself either with a calculator or with these answers:
- 465
- 62696
- 2251
Now you can try to apply your knowledge in the following subtraction examples:
- 6475 - 1763=
- 487673 - 466556=
- 756 - 364=
And here are the answers:
- 4712
- 21117
- 392
Now you can confidently solve addition and subtraction problems in columns.
