Difficult Brain Teasers

These brain teasers are rated our most difficult and challenging. Can you solve them?

Total matches: 11
Title  Detail  Rating  
I turn polar bears white... more>>>3.5 stars
Zebra PuzzleThis was supposedly created by Einstein, and some claim only 2% of the world can solve it.  There are 5 houses... more>>>4 stars
Does the water fall or rise... more>>>4 stars
The Three KnightsDuring the age of the medieval empires, when knights and barbarians fought against each other, a man was captured and sentenced to death for... more>>>4 stars
One Hundred CoinsYou are in a dark room with 100 coins on a table, 12 are heads and the rest are tails, and the two faces are completely indistinguishable... more>>>3.5 stars
Monty Hall ProblemSuppose you're on a game show, and you're given the choice of three doors: Behind one door is a car; behind the others, goats. You... more>>>3.5 stars
Every man in a village has cheated on his wifeEvery wife in the village instantly knows when a man other than her husband has cheated, but does not know when her own husband has. The... more>>>3.5 stars
Solved by preschoolers in 5 mins8809 = 6 7111 = 0 2172 = 0 6666 = 4 1111 = 0 3213 = 0 7662 = 2 9312 = 1 0000... more>>>4 stars
The next letterWhich letter should replace the question mark? OZW AO?WZ 11 ... more>>>3.5 stars
How would you weigh an aeroplane... more>>>3.5 stars
23 PrisonersA warden meets with the 23 prisoners when they arrive at the prison. He tells them: You may meet together today and plan... more>>>3.5 stars
Total matches: 11