Im pretty sure you would put 1/12 tablespoon of cinnamon in the cakes individually. You would divide 1/4 by 3. It's pretty simple. If that's not the answer I apologize dearly!
it'll be a graph like this. the blue line is y<-x+2 and you would shade everything below this line because it's less than. the green is y>x-3 so you would shade everything above this line because it is greater than.