I offered to make the cakes for our winter carnival supper this weekend. I need to serve 150. I have an 11x15 sheet pan and 9x13. They bought me 6 cake mixes. Should I make 6 9x13's or 3 11x15's? Will this be enough(no other desserts, just the cakes). I am thinking of making a carrot cake as well just to have another option.
thanks
Sandra

Take a look at this chart:

http://www.wilton.com/cake/cakeprep/baking/times/party_2inch.cfm

Most boxes of cake mix will give you about 5c of batter (pillsbury about 4-41/2) so you will get about 30 cups of batter from your 6 mixes. You'll need about 7c of batter for 1 layer 9x13. A 2 layer=45 servings and 11c of batter for a 1 layer 11x15. A 2 layer=60 servings. So you need more mix!