Celebrating with Software Geeks: Cutting the Cake

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Discussion Overview

The discussion revolves around the problem of cutting a rectangular cake into a prime number of equal pieces, exploring different approaches and interpretations of the problem. Participants engage in light-hearted banter while considering the mathematical implications of the cuts required.

Discussion Character

  • Exploratory
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant suggests that the cake should be cut into a prime number of pieces, proposing that only one cut is needed.
  • Another participant argues for zero cuts, stating that one piece is possible, while also noting that one is not a prime number.
  • A participant provides a method for cutting a 3 ft x 1 ft cake into three equal pieces using two cuts, challenging the feasibility of cutting a rectangular cake into three equal pieces.
  • There is a humorous exchange regarding the implications of cutting a chocolate cake, with one participant suggesting they would not bother cutting it at all.
  • Another participant emphasizes that the question implies a finite number of necessary cuts to meet the conditions of the problem.

Areas of Agreement / Disagreement

Participants express differing views on the number of cuts required and the feasibility of cutting the cake into a prime number of pieces. The discussion remains unresolved, with multiple competing interpretations and approaches presented.

Contextual Notes

Some assumptions about the cake's dimensions and the method of cutting are not explicitly stated, leading to varying interpretations of the problem. The discussion also touches on the playful nature of the topic, which may influence the seriousness of the mathematical reasoning.

Who May Find This Useful

This discussion may be of interest to those exploring mathematical reasoning in everyday scenarios, particularly in relation to problem-solving and creative thinking in informal settings.

DaveC426913
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I work with a bunch of software geeks. It was someone's brithday last week and we got him a cake, one of those white rectangular ones.

Someone joked about about many pieces he needed to cut it into, someone else made a joke about matricies.

I said he had to cut it into a prime number of pieces, all the same size and shape. How many cuts did he have to make?
 
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DaveC426913 said:
I said he had to cut it into a prime number of pieces, all the same size and shape. How many cuts did he have to make?

I vote for 1 cut!

DaveE
 
No cuts (zero) and one piece!
2 cuts and 3 pieces!
 
LAF said:
No cuts (zero) and one piece!
1 is not a prime number.
LAF said:
2 cuts and 3 pieces!
How will you cut a rectangular cake into 3 same-size same-shape pieces?


Out of a possible 1 points, your score is now -1. :biggrin:
 
DaveC426913 said:
How will you cut a rectangular cake into 3 same-size same-shape pieces?

Say the cake is 3 ft x 1 ft. Make two cuts, perpendicular to the long axis of the cake, at the 1 ft and 2 ft marks as measured from either end of the long axis. You have 3 1 ft x 1 ft pieces of cake.
 
loseyourname said:
Say the cake is 3 ft x 1 ft. Make two cuts, perpendicular to the long axis of the cake, at the 1 ft and 2 ft marks as measured from either end of the long axis. You have 3 1 ft x 1 ft pieces of cake.

Good one.
 
What's the answer if it's chocolate cake?
 
If it is a chocolate cake I will not bother to cut in such a fashion. Just have whole of it. This question has infinite answers.
 
ashishsinghal said:
If it is a chocolate cake I will not bother to cut in such a fashion. Just have whole of it. This question has infinite answers.

Not really. The question asks how many he had to cut. The implication is that the answer assumes no more cuts than necessary to meet the conditions.

Also, some answers are going to be trvially similar.They can be generalized using algebra to result in a small and very finite number of answers.
 
  • #10
For a white, rectangular cake:
a single cut which passes through the center of the cake will cut it into 2 pieces. Since 2 is a prime, this should suffice. The interesting thing is that it doesn't matter what angle the cut makes with the cake, the two pieces will be the same size and shape.
Chocolate cakes work the same.
 
  • #11
If the number of guests is the prime number p, you are forced to make p - 1 cuts that are parallel to each other.
The only exception is p = 2, where any cut through the center is ok.
[EDIT]
Note that the same holds for a circular cake where you would cut from the center outwards.
In this case the cuts do not need to be straight as long as rotational symmetry is observed.
In the rectangular case, all cuts need to be straight, because we need to observe translational symmetry and the sides of the cake are straight.
The exception is for p = 2, where any cut through the center works as long as it is point-symmetric.
[/EDIT]
-- I like ILSe
 
Last edited:

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