I placed the Surprise Birthday Cake item, and when i hovered over it, it showed me that there were 12 servings available. But when i had a sim grab a slide, the number went down to 4.27 servings, and...
Ideas
I noticed the same, something like 11.96 portions left after grabbing one piece (not sure about the number exactly, but it was close to 12 with two decimal places).