Did I goof?
I read it as a fairly bland question and assumed the questioner would expect nothing too refined by way of an answer.
In my former airline with the engines we fitted. ISA conditions, 240 tonne landing weight, air distance 3800nm to 5800nm (which spans roughly 8-12hrs) my estimate of fuel burnout for cruise in the M0.85-0.86 region is 9.80-10.40 tonnes per hour averaged over the whole or 78 to 125 tonnes burnout if you prefer. A climb to FL330 optimum I’d expect to consume somewhere between 6 and 8 tonnes if it is a smooth uncomplicated departure with 16-24minutes to settle at 2600-2800kg/hr/engine in first cruise for a good revenue earning payload. Supposing FL370 top of the drop and 240 tonne touch-down I’d expect pretty close to 2100kg/hr/engine final cruise. We can discuss reserves, holding etc too but I doubt that the original questioner wanted any more than a one line answer and hasn't come back for more Someone swotting up would certainly want more detail and look for a mate in eng ops to supply and not put their trust in an anonymous forum.
Best rgds
The "E"
Please don't shoot, I'm only the messenger!