Mary has a total of 216 eggs. she is filling cartons that completely 12 eggs each. how many cartons can she completely fill

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Total number of eggs that Mary has = 216
Number of eggs that can fit in each carton = 12
Then
Number of cartons required to completely fill = 216/12
                                                                        = 18
So 18 cartons are required by Mary to fill all the eggs that she has. I hope the procedure is simple enough for you to understand. You can always use this method for solving similar questions in future without requiring any kind of additional help from anybody.