Due March 14

This problem can be solved by carefully diagramming the possibilities. We consider this to be a hard problem, worth 20 points. Actually it is either very hard or pretty easy depending on how your mind works. Send answers and questions to mathstat@uoguelph.ca

A cruel Emperor in ancient Rome had a prisoner placed in an arena with three closed doors. Behind two of the doors were hungry lions, accustomed to eating prisoners. One door lead to freedom. The Emperor bade the prisoner to choose a door. Once the prisoner had chosen a door a centurion stepped into the arena and briefly opened a different door, showing a lion. The Emperor then told the prisoner he could open the door he had chosen or change his mind and open the third door. The question: should the prisoner have opened the door he first chose, opened the third door, or does his choice make no difference?

Send your answer to mathstat@uoguelph.ca

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