adding numeric entries and reset

This is what I'd like to do:

1. User enters 11 separate numeric values
2. They add up automatically as they are entered
3. Add a reset button to reset the numeric entries and the variable 

I've got it set up to work using Jeanette's example here: http://community.articulate.com/forums/t/14567.aspx

How do I add a reset button doing it that way? Can I do all this on one layer instead of two? 

Thanks!