Current time:0:00Total duration:7:25

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# Blue forehead room brain teaser

What happens when 100 perfect logicians have to figure out if they each have a blue forehead? Created by Sal Khan.

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# Blue forehead room brain teaser

Current time:0:00Total duration:7:25

0 energy points

What happens when 100 perfect logicians have to figure out if they each have a blue forehead? Created by Sal Khan.