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What Color Is My Hat?

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What Color Is My Hat?, a selection of answers from the Dr. Math archives.

What Color Hat am I Wearing?
Three students close their eyes, and the teacher puts a hat on each of their heads (hiding the other two hats)...

Red Hat, Blue Hat
A teacher puts one hat on each of three students' heads and then discards the remaining two hats so they cannot be seen. Then the first child is told he can look at the other two children and from the color of their hats, he can guess what color he is wearing...

Red and Blue Hats
Alan, Ben, and Cal are seated, with their eyes closed. Three hats are placed on their heads from a box that contains three red and two blue hats...

Probability and the Prisoner Problem
Each of 16 prisoners receives a hat that is either red or blue (the colour is selected randomly; each has a 1/2 probability). All the prisoners must simultaneously either try to guess the colour of their hats, or pass.

Gnomes and Hats
Ten gnomes in the dungeon of a castle of a tyrannical king are given a chance of survival...

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