What are the pan sizes that make up a 1/4, 1/2, 3/4 and a full sheet? Also, do you base your prices on one layer or two?

9x13 (1/4)
11x15 (1/3)
12x18 (1/2)
18x24 (full)
and my prices are for a single layer

My prices are based on double layer

Add'l FYI .... here's a link with an explanation of why they are called what they're called: http://cakecentral.com/cake-decorating-ftopicp-6799919.html#6799919

But I would avoid using the terms 'half' and "full". Cake civilians have no clue what those are, as evidence by my friend who asked me for pricing for a full sheet cake. I asked how many people he wanted to serve. He said 10. I said, "THen why do you need pricing for cake for 100?"

Or if someone asks, "How much is your half sheet cake?" then I ask, "How big a cake is that?" and they will reply "I don't know." (Then how the hell will you know if what I'm telling you is enough cake or if it's even a good price, ya big freakin' moron!?)

Also .... grocery stores are starting to put out 11x15's and calling them "half sheets" .... much like the 1/2 gallons of ice cream are now 1.5 quarts. So if a cake civilian is comparing your actual half sheet to the grocery's phony half sheet, then your cake will look more expensive.