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1500 questions
26
votes
3 answers
Why aren't the numbers playing nicely anymore?
The natural numbers have gotten in a big fight and split up into groups. If we can't get them back together again, the universe may never be the same! What kind of sense does it make to have three counting systems? No, they must be reunited.
You are…
Engineer Toast
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26
votes
14 answers
How did the man hang himself?
This may be simple and fairly well known, but I couldn't find it anywhere here, and felt it deserved a place in the ranks of puzzles
A man is found dead, hanging in an empty barn having committed suicide. The base of the barn was 20 feet by 30…
Aggie Kidd
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26
votes
3 answers
I can be 22 intrinsically and have a possible range between 22 and 96 (44 at the start)
I can be formed in many ways, and four parts are always involved. Sometimes the formation can happen with all four parts at once, but sometimes some parts come later than the others. The highest scenario (let's call this scenario I1) happens with…
pacoverflow
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26
votes
4 answers
Lions and Zebras on a Chess Board
The black knight is our lion chasing 8 white bishop zebras which can't capture. Can the zebras evade the lion forever, if team zebra positions all the pieces and has the first turn?
Rules:
The game is played on a standard 8x8 chess board
Zebras…
Bob
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26
votes
3 answers
A treasure hunt for the magic artefact
Somewhere in a magical land a small golden chest is delivered by an white eagle to a soon-to-be heroine. She opens it with shaky hands, knowing what it means that this gift has been delivered to her. Indeed, the first thing which falls out is a…
BmyGuest
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26
votes
7 answers
The population of Barberland
The Barberland Institute of Trichodemographic Research has published the following results:
Nobody in Barberland has more than 1,000,000 hairs.
No two inhabitants of Barberland have the same number of hairs.
Nobody in Barberland has the same number…
GOTO 0
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26
votes
1 answer
White is missing
All of the country flags below can be replaced by other flags. One country flag is missing and can not be replaced by another flag. Find the missing flag and explain why it's correct.
Prim3numbah
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26
votes
6 answers
Find a chess position that can occur twice but not thrice in a single game
For purposes of this puzzle, a chess position consists of an arrangement of pieces on the board, as well as the side to move. No other information about the game state is included.
The objective of this puzzle is to identify a position that can…
Elliot Glazer
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26
votes
12 answers
Tiling a Hexagon with Diamonds
A regular hexagon is divided into a triangular grid, and completely tiled with diamonds (two triangles glued together). Diamonds can be placed in one of three orientations. Prove that, no matter how the board is tiled, there will be the same number…
Mike Earnest
- 32,336
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26
votes
1 answer
26
votes
2 answers
The world's smallest square maze?
This puzzle is part of the Monthly Topic Challenge #14: Think inside the (very small) box!.
The smallest maze possible in a grid of squares would occupy a 2x2 grid (a 1x1 cell isn't a maze - it's a room...). Below is a contender for such a…
Stiv
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26
votes
1 answer
You'll find it if you go along the
Hidden below is a word. Which word is it?
(α-β)
--------
(AC)(LZ)
(AG)(PZ)
(SX)(GR)
(QC)(LP)
…
Prim3numbah
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26
votes
1 answer
Vivaldi's favorite
I am looking for a single word, that is missing. Everything you need to know, is right here:
953762581590 126971489190
2391402 2363595
158960430265 4657255395
3639090 126971489190
126971489190 3189841410
3627756834 27034799610
13949845 …
Lezzup
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26
votes
7 answers
Approximate pi out of small numbers
Given the numbers 1, 2, ..., n the puzzle is to try to make a number as close as possible to pi using only the four mathematical operations +, -, *, / and parentheses (brackets). You don't have to use all the numbers and you are not allowed to stick…
Simd
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26
votes
2 answers
Any fans of The Big Bang Theory?
Penny, Sheldon, Howard and Leonard are chilling. Sheldon comes up with an idea to play a dartboard game. Like always, he has his own rules. He brings a weird dartboard from his room, sets the bullseye on fire and hangs it on the back of the door. He…
Techidiot
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