Choose Table - Insert Table, and insert a table with one column and more than one row into a text document.
Type a number in each cell of the column, but leave the last cell in the column empty.
Place the cursor in the last cell of the column, and then click the \<emph\>Sum\</emph\> icon on the \<emph\>Table Bar\</emph\>.\<br/\>The\<emph\> Formula Bar\</emph\> appears with the entry "=sum".
Click in the first cell of the series you want to sum up, drag to the final cell, and then release.\<br/\>LibreOffice inserts a formula for calculating the sum of the values in the current column.
Press Enter, or click \<emph\>Apply\</emph\> in the Formula bar. \<br/\>The sum of the values in the current column is entered in the cell.
If you enter a different number anywhere in the column, the sum is updated as soon as you click in the last column cell.
Similarly, you can also quickly calculate the sum of a row of numbers.