I know this has been discussed before but I cannot find it at present. How do you calculate the # of servings for a 14", 10', 8", and 6" ?

here is a serving chart for different sizes and shapes, not sure if you're talking round or square cakes, but this should help

http://www.wilton.com/cakes/making-cakes/baking-wedding-cake-2-inch-pans.cfm