Cake Division Puzzle: Max Amount for 1st Person

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In the Cake Division Puzzle, two individuals divide two identical cakes under specific rules, with the first person aiming to maximize their share. The first person can divide the first cake into two pieces, and the second person chooses which cake to pick from first. A proposed strategy involves dividing the first cake into two pieces of size k and 1-k, where k is less than or equal to 1/2. If the second person selects the first cake, they receive the larger piece, leaving the first person with the entirety of the second cake. The maximum amount the first person can secure is determined to be 1-k if k is optimally chosen.
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Homework Statement


Suppose that two people are dividing two cakes using the following rules:
1. The first person divides the first cake into two pieces in any fashion.
2. The second person then chooses which of the two cakes they will get to choose the first piece from.
3. The first person then cuts the second cake into two pieces in any fashion.
4. The second person chooses his piece of whichever cake he chose in step 2.
5. The first person chooses his piece of the other cake.

Devise a strategy that gives the first person as much cake as possible and say what that maximum amount is. Assume both cakes are the same size.

The Attempt at a Solution



The idea I think is multivariate calculus, seeing as that's what we are studying at the moment, but I also think this is just my prof being clever... I figured not cutting the cake at all would allow the first person a whole cake no matter what, but I'm not sure if that's allowed. Has anyone seen this before?
 
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Nobody has any idea?
 
Suppose the first cake is divided in 2 pieces of size k and 1-k with k<=1/2

If the second person chooses the first cake, he can get the largest piece of cake #1. He won't get anything of cake #2 because the first person can divide AND choose. So the second person ends up with (1-k)

If the second person chooses cake #2 he can get the smallest piece of cake #1 and half of cake #2, so the second person gets (1/2)+k
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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