What is the best way to figure the number of servings that are left in a 3-D cake after you have carved the shape?
I usually leave my carvings on a plate, so I can see how much I took away. I would estimate how many servings of cake you carved away, and subtract from the intact cake.
you could weigh it before carving and weigh the cake after carving. based on the weight and number of servings before carving you can figure out what you're left with.