Dividing a cake into equal thirds riddle - no not what you think

Ok seriously, here is how you do it.
Let's make the cake rectangular, although it doesn't matter, it's easier to visualize the solution.

A holds his knife facing north to south (or straight out) and moves his knife very slowly hovering from the top of the east corner towards the top west corner.
At any time A can start cutting north to south and take his piece, or before that B or C can yell "Stop" and at that point A has to cut (north to south) and then whoever yelled stop has to take that piece. Then out of the 2 remaining people without cake, one starts the same hovering movement with the knife and he can start cutting his piece whenever he wishes unless the last person yells stop once more in which case he has to take the piece. The final piece goes to whoever is left.

This is prone to human error of course as the person who holds the knife could cut early and get a smaller piece or the person watching waiting to possibly yell stop could say stop too early and get a smaller piece. But in the end they all have control over how it is cut so it is fair and if they all want the biggest piece and have a keen eye they will end up with 3 equal pieces.
There is no way to collude or cheat anyone.
 
Dixie. The repeating decimal on a 1/3 is just an artifact of using base 10 arithemetic. Thirds can be equal. It;'s not an impossiblity you stupid fucking cunt.
 
Republican approach. I've earned all the cake and are more deserving of all the shares you commie socialist have done nothing to earn.

Democratic approach. We must cut this cake into 300,000,000 equal pieces.

Liberatrian approach. Set the cake free!!
 
The number of pieces would be equal, but not the volume of cake.

Each of the 12 pieces would be .08333333 of the whole cake, except for one piece, which would have to be .08333334 to include the entire whole cake. Of course, none of the recipients would be able to tell the difference in a piece of cake .00000001 larger or smaller than the others.

You really want to go here again?

One detail he forgot to mention is that the cakje weighs 3 lbs. Each person gets one pound. No 0.000000001 remainder or anything so stupid.

It is divided evenly.
 
Ah, the Obama plan.

The hotel clerk was busy at the counter.....a rich tourist bustles in the door..."Look, I know I haven't got a reservation, but I simply have to find a room for the night"...

"I'm sorry sir, but that is impossible! We're booked up!"

The tourist lays a hundred dollar bill on the counter..."Are you sure?"

Clerk eying the bill "Well, I tell you what. Room 318 is closed for remodeling. Take this key and take a look. If it suits you, you can have it for the night" The tourist takes the key and gets on the elevator.

Just then a man bursts into the lobby. He is angry. It's the baker. He tells the clerk "You haven't paid me for two weeks! If I don't get some money you get no rolls for your continental breakfast tomorrow!".

The clerk looks at the hundred dollar bill. He calculates the tourist is desperate, certainly he will take the room...."Here! Here is a hundred dollars on our bill"...the baker takes it and leaves....

Hardly is the baker out the door when he runs into his bookie....."There you are John. We need to discuss that hundred dollars you owe me on last nights game. Ohio State lost, you know." He cracks his knuckles knowingly.

"Yes, I was just coming to see you. Here it is!" The baker has broken out in a sweat.

The bookie crosses the street to the lawyer's office. Oddly, the door is locked, though the lawyer is usually in around this time. He knocks.

The lawyer comes to the door, a bit disheveled, he sticks his head out. "Here's that hundred you needed for a retainer. Get started on what we discussed." The lawyer agrees and ducks back inside.

A few minutes later a hooker steps out of his office, tucking a hundred dollar bill under her bra. She crosses the street and walks into the hotel.

"Hi Fred. It's the first of the month, here's your hundred. and thanks for the tip about the Broker's Convention. I really cleaned up." She lays the hundred dollar bill on the counter.

Just then the elevator opens up and the tourist steps out. He picks up the hundred dollar bill and says "Sorry, that room simply will not do" and leaves.

The difference between my story and Obama's plan is that in my story, only the lawyer got screwed.
 
3 people are dividing a cake. Each person wants as much cake as possible for himself, but each person thinks that the other two might be colluding. Lets call the three A, B, and C.

A suggests that he will cut the cake into 3 portions, and then C will pick his piece from the 3, and B then would pick his choice from the 2 remaining. and A takes the last piece. B objects to this scheme, saying that A can cut the cake into 1 large piece, and 2 smaller equal pieces. C then would have the largest piece, and B would have to take the smaller piece. In fact, B claims, If A and C were really colluding, this method would allow them to get the entire cake to share among the two of them.

Given this distrusting atmosphere, is there a way to divide the cake so that each person is satisfied? Any proposed method would have to convince each person that he would get his fair share even if the other two were colluding.

Divide the cake into infinity pieces. Give each person a 1/3 of infinity pieces.
 
Ok seriously, here is how you do it.
Let's make the cake rectangular, although it doesn't matter, it's easier to visualize the solution.

A holds his knife facing north to south (or straight out) and moves his knife very slowly hovering from the top of the east corner towards the top west corner.
At any time A can start cutting north to south and take his piece, or before that B or C can yell "Stop" and at that point A has to cut (north to south) and then whoever yelled stop has to take that piece. Then out of the 2 remaining people without cake, one starts the same hovering movement with the knife and he can start cutting his piece whenever he wishes unless the last person yells stop once more in which case he has to take the piece. The final piece goes to whoever is left.

This is prone to human error of course as the person who holds the knife could cut early and get a smaller piece or the person watching waiting to possibly yell stop could say stop too early and get a smaller piece. But in the end they all have control over how it is cut so it is fair and if they all want the biggest piece and have a keen eye they will end up with 3 equal pieces.
There is no way to collude or cheat anyone.

B and C could collude to not yell "stop" until the piece is literally the whole cake. Then they could split that piece.

The only fair way I can think of would be to have one person cut the cake and have the cake divided out to each person by random lottery. The person could cut the cake unfairly, but it would provide them no advantage to do so.
 
The number of pieces would be equal, but not the volume of cake.

Each of the 12 pieces would be .08333333 of the whole cake, except for one piece, which would have to be .08333334 to include the entire whole cake. Of course, none of the recipients would be able to tell the difference in a piece of cake .00000001 larger or smaller than the others.

Who do you think you are, a pholosophy professor, only an idiot would not underatand that a mathimatical concept and a cake are two different things.
 
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