Hi everyone! So I am making a baby shower cake for that will be served in a catering hall. I am thinking of a tiered cake but Im not sure how many tiers and what sizes they should be. I am putting a 6" "baby butt" on the top but I'm not sure if I should count that with the servings. I was thinking a 12",10" and then the 6" butt on the top, but Im not sure. If anyone can give me any type of direction I will greatly appreciate it!!! 

How many servings do you need? a 12" is around 60-65 if I remember correctly.

http://www.wilton.com/cakes/making-cakes/baking-serving-guide.cfm

I'm doing a 12" round in a few weeks and it will serve 40 according to this chart. 

Than you so much for getting back to me! It needs to feed 100 people and Im tossed up between a 10",8", with the 6" baby butt or a 12",10" and 6" baby butt?

I have 45-56 servings for a 12" using 1x2xheight of cake. Maybe the wilton one is party servings, which are larger? The 1x2 is a lot of cake when you cut it as long as the tier is 4" tall or more.

Anyway, you only need about 80 servings for 100 people, so any combination that will give you 80-90 servings will work. I think the 12-10-baby butt will probably be better than the 8-10 if you're trying to get close to 100 in either direction.

Thank you so much @costumeczar  !!! I appreciate it so much!

It depends on who's cutting the cake, too. If the chart @Webake2gether  is using is the party serving chart and they cut it like that, you DEFINITELY want to go with the bigger tiers because they'll cut the pieces larger.

It was the party serving chart. There is also wedding servings on there. I'd also go with 12" 10" and 6" just to be on the safe side . 

Yeah, because my son would cut a 12" cake into four pieces and say it was four servings...

@costumeczar Our sons must have taken the same "cake cutting course" or made their own chart. 

It's a special chart that only exists in the minds of teenaged and 20-something boys