I think it is 3 djdodnekosowje
Isnt there a youtube video with that? Im not sure... But thats where ill look for proof.. :)
Answer:
Words for dividing:
The problem is asking you to divide, because the key word is, "fill empty egg cartons that each hold"
So Mary will fill each carton with 12 eggs each until she runs out.

<em>12 goes into 216 eighteen times exactly.</em>
<em />
<em>and the result is(R means leftovers, which are none here)...</em>
<em />
(12,1):12³+1³=1728+1=1729
(10,9): 10³+9³=1000+729=1729
☺☺☺☺