I just use the common sense!
A) Cut the apple in to three. First I offer it to the Arahant then chid and I have the rest.
B) If you insist that I should give the whole apple to one I will give it to Arahant. I know he will cut that into three and will be shared.
When I go to my local temple the monk always offer me food, tea and coffee.
C) I haven’t met an Arahant but I know that he/she will not be plump.