I think we have to have a practical definition of which group a point on the line is in.

You could go with neither, or both (I'd suggest "both").

Then if you put the 3rd point off the line, that half-plane has 3 points of that color, and the other half-plane has 2 points. "At most" -- well, you can't split a point, so it "at most" must be ceil(n/2).

On the other hand, choosing "neither" means that one side has 1 point, and the other side has 0, each of which is "at most" n/2. <p. We just have to get the definitions right.

-QM
--
Quantum Mechanics: The dreams stuff is made of

In reply to Re^6: Puzzle: The Ham Cheese Sandwich cut. by QM
in thread Puzzle: The Ham Cheese Sandwich cut. by Perl Mouse

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