would this work/feed 100 people

[gallopinghorse]

I have been asked to make a christening cake to feed 100 people. It needs to be a rectangular single layer cake. I am a very amateur cake maker and have never made anything of this size.
I have a 12" by 12" cake tin and was wondering if I baked two cakes and placed them side by side whether this would be large enough so the dimensions would be 24" by 12"

thanks

Id say a slice would be one inch by two inches. So if it were 12 x 24 thatd be 144 peices.

Agree with ThinkIveBeenHacked, a portion is generally 1"x2" for a sponge cake, or half that (and therefore double the portions) for a fruit cake.

Covering a cake of that size will be really really difficult though - why does it have to be one layer? And if it really does, I'd just do a 'normal' sized display cake plus a plain cutting cake to make up the portions.

thanks for replies that was just what they asked for. Not sure how else to go about it. Never done a cake for 100 before

I've made a 12 inch cake before and covering it without ripping the icing was a bit of a challenge , in the end I rolled the icing on my dining table ( think it was 1.5 kg or maybe 2) and then I got a friend to lift one side, I lifted the other and then another friend quickly pushed the cake underneath and we lowered it down. Worked a treat!