How to use text as numbers in Deluge

How to use text as numbers in Deluge

Sorry, I'm not a programmer or I might have tried more to figure this out.

I have two number fields: "Width" and "Height". I need to multiply them to create formula with area. This is no problem: (Width * Height)

I also need to create text that reads "8.5x11". I've tried creating a formula using combinations of single-quotes, double-quotes, and +. How to I treat number fields as text and operate on them as text?
helsten