hi i'm making a fondant cake for my daughters are all the large size cake dummies the same size i'm going to use that for the bottom, the next size pan is going to be  about 2 inches in, if i make this one with 3 or 4 layers and the top with one or 2 will it be enough for 70 people, or do you have a suggestion on how many layers to stack Thank you

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

thank you i copied and pasted it to  my files