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Brain teasers

10 videos
Random logic puzzles and brain teasers. Fun to do and useful for many job interviews!

Heavier ball

VIDEO 5:26 minutes

Liar truth-teller brain teaser

VIDEO 6:49 minutes
How to get correct advice when you can only ask one question from either a liar or a truth-teller (when you don't know who is what)

Toggler brain teaser

VIDEO 11:12 minutes
Separating the truthteller from the togglers!

Alien abduction brain teaser

VIDEO 16:59 minutes
Saving Earth from becoming a mushroom farm.

Blue forehead room brain teaser

VIDEO 7:25 minutes
What happens when 100 perfect logicians have to figure out if they each have a blue forehead?

Blue forehead room solution

VIDEO 11:00 minutes
Do not watch before Blue Forehead Room. THIS IS THE SOLUTION!

Forehead numbers brain teaser

VIDEO 12:09 minutes
The perfect logicians are at it again.

Light bulb switching brain teaser

VIDEO 11:19 minutes
Turning light bulbs on and off.

Path counting brain teaser

VIDEO 10:42 minutes
Counting paths in a square

3D path counting brain teaser

VIDEO 12:15 minutes
Extending the path counting to three dimensions