Addition question.

I am using the following to display a table full of infomation: while(list($var1,$var2,$var3)=mysql_fetch_row($result)) { printf("<tr> <td>$var1</td> <td>$var2</td> <td>$var3</td> </tr> "); } Based on search criteria, $var3 can be returned 1....X amount of times and likely will have a different value each time. I want to total up these values. Could someone provide me with assistance along those lines? thanks!