Adding number values in one column to show total in another column

I am currently designing a web page template to create "personas" of clients and their monthly billing charges. What I would like to do is have the charges listed in their own boxes/columns (Circle #1) and then those charges added to the total on the right hand column(Circle #2) I've been searching around the web but can't seem to find any answers.

http://ift.tt/293OJaG

Thank you