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Filtered by tag: logic

41 29 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 ...
logic mathematical Submitted by Aakash
Hard
7.6
30 7 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 ...
Doable
4.3
28 20 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 ...
Easy
2.4
22 19 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 ...
logic brain teaser Submitted by Valentin
Doable
6.0
17 4 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). ...
Doable
3.8
15 6 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 ...
logic mathematics Submitted by Nikhil
Doable
6.3
11 1 Choose the Next Letter
Choose the next letter in the sequence: O T T F F S S ?
logic patterns sequences Submitted by Ravi
Easy
3.1
8 1 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 ...
Hard
10.0
8 2 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 ...
logic brain teaser Submitted by Ravi
Doable
3.3
8 5 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 ...
logic brain teaser Submitted by Valentin
Hard
8.4
7 3 Tea and Wine
You take a spoon of wine from a barrel of wine and put it into your cup of tea. Then you return a spoon of the (non-uniform) mixture of tea and wine from your cup and put it in the barrel. Now you ha ...
Math logic Submitted by Ravi
Doable
4.9
7 12 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 ...
logic prisoners hats Submitted by Aakash
Hard
8.7
7 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?
logic brain teaser Submitted by Valentin
Doable
5.6
6 6 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 ...
Hard
7.3
6 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 ...
Math logic unsolved Submitted by Aakash
Hard
8.7