Logic riddle

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Hi all,

I recently came upon a new answer to a very common riddle, that surprised me, as I understand the rationale, but would have decided for another answer.

Here is the problem:

Let's say two people want to share a cake in a "fair" way.
We want to find a "fair" process so they are both treated fairly.
The answer is:
1. Person1 cuts the cake
2. Person2 chooses the share that he wants
3. Person1 takes the other share.
The result is that Person1 has an incentive to cut the cake in a "fair" way, i.e. half half.

Now the question I found a new answer to is the following:
We now have 3 people who want to split the cake in a "fair" way.
How should they proceed ?

Please let me know your thoughts... Curious to see which solution is the most popular.

With a compass, of course.

1 cuts, 2cuts, 3 chooses, 1 chooses, 2 takes the last.

I tire of this rudimentary game theory.

In my opinion they should just cut them all equally straight off. It's just easier.

I think the best method is this: One person cuts three pieces. The two others name those that they would be willing to take. If their selections do not necessarily conflict (ie, both would accept two of the existing three) then each takes one of those they had named and the divider takes the remaining piece. If they do necessarily conflict (ie both would only accept the same one), then the divider takes one of the other two pieces and the two remaining pieces are "recompiled", cut by one of the two choosers, and the other of the two then chooses a piece, leaving one for the second cutter.

The solution is the same. Almost. My grandmother had five kids and exercised this principle every night in her home.

One cut, another served. Period.

When you know someone else will be serving, you will always make sure the pieces are all the same so the server doesn't take the largest one.

Now if you want to start speculating on conspiracy theories, all bets are off, and there are no reliable solutions, because in the case of possible conspiracies, the possibilities are practically endless, and for every solution you come up with, there is a conspiracy that can get around it.

...Why am I the only one who's said anything remotely sensible?

Make sure you cut 120 degree angles, and make sure they meet in the exact center. Then you're certain it's absolutely fair. There are plenty of tools for this job. Go ask an engineer.

The stronger of the three people beats up the other two people and takes all the cake.

The more cunning one tricks the other two by convincing each of them that the other is the greatest threat, sneaking off with the cake while they fight each other.

The better craftsman constructs a superior weapon to the other two and convinces them via old-fashioned might is right to give up their claims to the cake.

And so on.

Each of these solutions could be considered "fair".

Waddya mean? You need a lot more than just a compass for this. You need a compass, a protractor, four tape measures, a plum-bob, sextant, and an x-ray machine to make sure nobody's hoarding anything under their clothes. Did I forget anything?

Well, this relies on the assumption that the cake is a perfect circle.

I confess, that's not my area of strength. I'm just pointing out that involving everyone isn't the way to make it fair; being precise in cutting it is. Because with the best intentions in the world, you might still cut it wrong.

And anyway, an x-ray wouldn't help; it wouldn't detect the cake, which is soft.

ok now the cake is cut, who decides on the piece with the flower

You've obviously never had my grandmother's cake!

You poor thing, MrXxx. I pity you, if that's your only experience with cake.

(By the way... doesn't your name end up blocking this site for certain people?)

Nah. Just had some great cake last night my son made. One grandmother died when I was pretty young, and I don't remember if I ever even had cake made by her. My other grandmother never made cakes, but baked a really mean pie.



Huh! Never even thought about it. Could be if somebody's running a parental filter, but then, it's probably not a big deal if a filter like that is blocking this site given some of the stuff that goes on here. It's actually a Ray Bradbury character from the Martian Chronicles.

The person with the most steady hand cuts the cake into the closest appoximation of thirds and everyone eats the piece they are given with thanks and gratitude that they even have a piece of cake to be begin with. Anyone who whines about unfairness, gets their piece of cake confiscated and fed to the dog who will appreciate it more.

Moral: Life isn't fair. Deal with it or perish.

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