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 7 Burning Rope There are two lengths of rope. Each one can burn in exactly one hour. They are not necessarily of the same length or width as each other. They also are not of uniform width (may be wider in middle th ... Submitted by Ravi Doable 4.3 7 Psycho Killer While at the funeral of her mother, she met a man whom she did not know. She thought he was amazing, her dream guy, and she fell in love with him but never asked for his number and could not find him ... Submitted by Valentin Easy 3.0 18 3 Men and a Hotel Room Three men decided to split the cost of a hotel room. The hotel manager gave them a price of \$30. The men split the bill evenly, each paying \$10, and retired to their room. However, the manager real ... Submitted by Valentin Doable 4.2 7 The bus stop You’re driving your car to work in the pouring rain when you see three people on the side of the road at an uncovered bus stop. You recognize one as your best friend waiting to go to work, the second ... Submitted by Aakash Doable 4.7 9 Three Idols Here's a classic: Three gods A, B, and C are called, in some order, True, False, and Random. True always speaks truly, False always speaks falsely, but whether Random speaks truly or falsely is a comp ... Submitted by Aakash Hard 9.1 5 Don't Eat Me! Would you rather a crocodile attack you or an alligator? Submitted by Aakash Doable 4.9 8 The Famous Hole in a Sphere This incredible problem was first made famous by Martin Gardner with his ‘Mathematical Games’ column published in Scientific American throughout the 60s and 70s. A cylindrical hole, 6 inches long, ... Submitted by Ravi Hard 6.7 5 Cards With Crosses You have a stack of 23 cards. Each card has an image of a cross on one side, and an image of a circle on the other side. You know that 14 cards in the stack are laying with the cross up, and therefor ... Submitted by Valentin Doable 6.0 3 The fake coin You have 9 coins which all look identical but 1 of them weight less than the others. You have a two pan balance (see the picture) with which you can measure twice, and with this 2 measurements you ha ... Submitted by Aakash Doable 3.5 4 Surgery A boy and his father get into an enormous and unfortunate car accident. The father is taken to one hospital and the son to another. The boy’s surgeon walks into the hospital room and says “I cannot ... Submitted by Valentin Doable 3.3 7 Clock Works - Google Interview Question How many degrees are there in the angle between the hour and minute hands of a clock when the time is a quarter past three? Submitted by Valentin Easy 3.1 3 Open Water A man is in a rowing boat floating on a lake, in the boat he has a brick. He throws the brick over the side of the boat so that it lands in the water. The brick sinks quickly. The question is, as a r ... Submitted by Valentin Doable 6.0 2 The North Pole Bear Puzzle Reloaded A man walks 1 mile south, then 1 mile east, and finally 1 mile north to find himself in exactly the same position as he started. He is NOT at the north pole, nor does he shoot a bear. Where is he? ... Submitted by Ravi Doable 6.0 8 Attic Lamp Switch A downstairs panel contains three on-off switches. One of them controls the lamp in your attic. Using only ONE trip up to the attic, how do you determine which switch controls the lamp? Submitted by Valentin Doable 5.3 5 3 Brilliant People There are three genii standing in a row in a room facing the same direction. Thus, the genius at one end can see the two genii ahead of him, the genius in the middle can only see the one genius ahea ... Submitted by Ravi Doable 4.3