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

0 energy points

# 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.

If you're seeing this message, it means we're having trouble loading external resources on our website.

If you're behind a web filter, please make sure that the domains ***.kastatic.org** and ***.kasandbox.org** are unblocked.

Main content
# 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.