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 56 All the King's Wine So there's this king. Someone breaks into his wine cellar where he stores 1000 bottles of wine. This person proceeds to poison one of the 1000 bottles, but gets away too quickly for the king's guard ... Submitted by Aakash Hard 7.5 46 Charlie and the Chocolate Factory Charlie once visited chocolate factory to buy some chocolates.Chocolate cost Rs. 3 each and he had only Rs. 45.He was disappointed. He wanted more. But when he reached the factory he was amazed. There ... Submitted by Mikit Kanakia Easy 2.4 45 The Sinking Island You and 3 friends are on an island that is sinking. There is one bridge from the island to the mainland that supports at most 2 people at once. However, it's dark outside so anyone crossing the bridge ... Submitted by Ravi Doable 4.3 28 12 Identical Balls You have 12 identical balls. One of them is slightly different in weight than the rest. You have three weighs of a balance scale to determine which ball is different and whether it is heavier or li ... Submitted by Valentin Doable 6.2 21 Odd Pills Your pharmacist gives you 5 jars filled with pills. The pills contained in each jar have an identical appearance and size (i.e. if you mixed all of the pills you wouldn't be able to tell them apart). ... Submitted by Jay Elliott Doable 3.6 19 Going to the Track The London racetrack needs to submit its top three horses to the Kentucky Derby next month in order to compete for a prize. However in a recent electrical storm, all the racetrack's previous race histo ... Submitted by Nikhil Doable 6.2 13 Black and White Hats There are 100 prisoners in jail. Their guards decide to play a game with them. Here's what happens: 1) The prisoners are lined up in a single file, front to back, such that the prisoner at the back of ... Submitted by Aakash Hard 8.5 12 Choose the Next Letter Choose the next letter in the sequence: O T T F F S S ? Submitted by Ravi Doable 4.0 11 Measuring Up You have a 3 and a 5 litre water container, each container has no markings except for that which gives you its total volume. You also have a running tap. You must use the containers and the tap in su ... Submitted by Ravi Easy 3.1 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 8 Non-Adaptive 12 Identical Balls Okay - so I posted this puzzle to reddit a few weeks ago and one guy had the following comment: Same problem, but your solution must be non-adaptive. IOW, specify the weighings that you will make up f ... Submitted by Aakash Hard 9.0 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 8 Prisoners and hats 100 prisoners are standing in a line each 1 seeing the back of the ones in front of him. Each prisoner is given a black or a white hat. If they can guess the color of their hat they can go away freel ... Submitted by Valentin Hard 8.5 7 Cooking Time A cook must put a souffle exactly 9 minutes at the oven, but he only have a 7 minutes hourglass and a 4 minutes hourglass. How can he measure 9 minutes with those clocks? Submitted by Ravi Doable 5.7 7 The Neighbourhood People say Einstein suggested that 98% of the world’s population couldn’t figure out the answer to this puzzle. It is not for the faint of heart: There are 5 houses each with a different color. Th ... Submitted by Aakash Hard 7.5