Pentominoproblem in Finland
During a speech at the conference bridge

was my attention more to someone next to me.

The first problem is about the box 'Escher's fishes'
It's in the book "M.C. Escher Caleidocycli" from Doris Schattschneider and Wallace Walker.
Color the fishes using four different colors such that no exist two adjacent fish have the same color.


In the box are five pentacubes


This is a second problem: 5-1 = 2+2 of Wei-Hwa Huang
From these five pentacubes, leave out one and form two identical (congruent and same orientation) shapes with the remaining four (2 + 2) pieces.
Will you know which pentacube you must leave out?


It is also a puzzle to put the pieces back in the box.

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