I've discovered the easiest way to do this is when they ask together or separate, say together. When the bill comes we use plastic (debit cards - I track my spending so much better with it). I jot on the bottom of the check this card, this much, that card, that much.
It must be easy for the waitstaff to do, becasue we've never gotten even an eye-roll doing this. It's easier than trying to get cash right for all parties.
As for the OP's bill. Wow, that wasn't V&A's, was it? I'd have to say separate with that group.
If you've got a pattern with people splitting is fine, but three glasses of wine usually equals a nice entree.
Ronda