Total of Fields Inside a Row

SSRS 2008 R2

I have a simple report table

Name, Total Amounts, Comments

Co #1, 10, Comment
Co #1, 15, Comment
Co #2, 12, Comment

What I need is to add together the 10+15 and display as a total in a single row for each comany where there are multiple values to add together. So there is one row for Co #1 like so:

Co #1, 25, Comment

I looked into using SUM but it doesn't seem to work the ay I expect. Do I need to make this calculation part of my query? (new to reporting)