My form calculation widget stopped working

The widget that performs the addition to my form stopped working.  I changed it from numerical to letters and it worked, but not for any numbers.  I added another box to start from scratch, but it did not work either.  Is this something that you handle or do I have to go to the widget builder?

I've fixed it by removing the + at the end of the equation. Please check again. 

Aaah man, you couldn't tell me you spent hours rewriting code or something? Anyway, thanks. You guys are the best.

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