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Encyclopedia>Numbers and Quantities>Arithmetic>Addition and Subtraction>How to Add Using the Column Method

A row is a collection of cells or items on a horizontal line. A column is a collection of cells or items on a vertical line. Think about all the different terms in math as names for your new friends. This will make it easier to remember them.

The general setup for addition looks a bit like a tower, because the numbers are placed above each other in columns. Arranging the terms like this is called the column method. The digits in the number follow the positions in the place value system, and appear below one another in a calculation: The ones position is underneath the ones position, the tens position is underneath the tens position, and so on.

Example 1

The Column Method

Calculate $2198.4335 + 5901.5251$

2198.4335 + 5801.5251 = 7999.9586 solved using the column method

Rule

Instructions for Addition Without Transferring Tens

1.: Make sure to set up the numbers according to the column method.
2.: When adding numbers together, you add together the numbers in the different places in the place value system.
3.: Start with the column furthest to the right. Add each column together. If a number is missing from a place, you can imagine a $0$ in the empty place.
4.: When you’ve added a column together, write the answer in that same column, but underneath the line.
5.: Do this for each column from right to left until you’ve run out of columns.
6.: If the answer in the final column consists of two numbers, write the entire answer underneath the line.

Example 2

Calculate $89 + 10$ , $627 + 142$ and $98.43 + 31.52$

672 + 142 = 769 solved using the column method 98.43 + 31.52 = 129.95 solved using the column method

Rule

Instructions for Addition with Transferring Tens

1.: Set up the numbers according to the column method.
2.: When adding numbers together, you add the numbers with the same place values together.
3.: Start with the numbers furthest to the right. Add each column together. If a number is missing from a place, you can imagine a $0$ in the empty place.
4.: When you’ve added a column together, write the answer in that same column underneath the line. If the answer in the column is greater than $9$ , put the number in the ones place in the answer underneath the line and the number in the tens place on top of the column to the left. This is called transferring a ten.
5.: When you add the next column together, remember the number you put on top of it if you transferred a ten from the previous column.
6.: Keep going from right to left column by column until you run out of columns.
7.: If the answer in the final column is larger than $9$ , just write it underneath the line as it is.