I'm late to the conversation but this is what I/we consume using a single burner Coleman.  For two of us we use approximately one, one lb. tank every three days.  This includes coffee, breakfast prep and a nightly fish fry along with the misc. apple cider, etc.  The fish fry consumes the vast majority of that usage.  I never did the actual burn time ( thanks Jimbo, I'll be using that).  One solo trips I use one half that amount or one lb. every six days.  As stated by others.....it all depends on what you're cooking.
Safe travels......Mike