3 stone by xmas

Ok so ive just joined a pledge to lose 3 stone by christmas, what do you think my chances are?
The odds were against me this morning i turned up at work to find the guy who works in our kitchen was off sick, so muggins here as any good manager would stepped up to the breach. Yes i merrily made sausage, bacon and egg butties not to mention pies and cakes but i was a good girl and remembered munches notion of me losing a stone by next sun and left well alone. Bl**dy hard though, this sort of thing doesnt seem to get any easier.