According to Selfridge and Conway, 3 people’s method is as follows.(See ref for graphical intuition. And refer to wikipedia for more formal description.)
- Alice cuts [into what she thinks are thirds].
- Betty trims one piece [to create a 2-way tie for largest], and sets the trimmings aside.
- Let Chuck pick a piece, then Betty, then Alice. Require Betty to take a trimmed piece if Charlie does not. Call the person who tooked the trimmed piece T, and the other (of Betty and Chuck) NT.
- To deal with the trimmings, let NT cut them [into what she thinks are thirds].
- Let players pick pieces in this order: T, Alice, then NT.
My questions are
- How about to let T cut the trimmings(in step 4. Accordingly, step 5’s order would be NT-Alice-T.)?
- How about to change the order of step 5 to T-NT-Alice ?
Are These OK?
UPDATE : I realized why T-NT-Alice order (in step 5) is unfair. In this case, Alice can envy NT. Then Question 1 remains.
Ad 1.
After step 3 Alice thinks, that she nad NT have the same portion of cake.
If we let T to cut trimmings, then in step 5 we have two possible orders (T takes the part as the last one):