Questions tagged [three-dimensional]
This tag is used for geometric puzzles, if one wants to stress that the setting is not 2-dimensional but 3-dimensional.
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How can this shape perfectly cover a cube?
The following shape:
can be folded onto the surface of a cube in a way that perfectly covers the entire cube with no gaps and no overlaps.
How can this be done?
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The brain-curdling eldritch horrors and the third dimension
We're in the year 2016 so it's finally time to take puzzles to the 3rd dimension!
So let's see what those beautiful times bring us today:
(click to enlarge)
Everyone of you clever sods could as ...
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Can you perfectly wrap a cube with this blocky shape?
The following blocky shape:
can be folded onto the surface of a cube in a way that perfectly covers the entire cube with no gaps and no overlaps.
How can it be done?
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Six pyramids in a cube
This question is from the German mathematics competition Känguru der Mathematik. In this competition students have to solve 30 mathematical tasks like this in 90 minutes without calculator. Actually ...
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A-maze-ing Dice
This is an entry to the 12th fortnightly challenge
"So you have escaped my labyrinth of words, and now you think you are free, do you? Well, I have news for you: Think again! Ha Ha Ha Ha"
...
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Can you refold a hyper plus sign into a cube?
If you take a cube, and grow a new cube out from each of its six faces, you will get a "hyper plus sign":
This 3D solid has an interesting property. It can be sliced along its edges and ...
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Sometimes force is the solution [RTFM]
This time we are investigating a well secured safe. Simply breaking it is not possible (I've tried). We need to find the right combination!
Can you help me open it?
Along with the ...
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Red Herring Bonkers In The Red Herring Bunkers
Please help me!
Last weekend I hosted a hell of a party at my workplace (I'll invite you next time, promise). Of course, my boss didn't know about it.
The next morning I entered the building and ...
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Sudoku on a Mobius Strip
Well we've done sudoku on keyboards, so the next step is obviously putting a Sudoku on a Mobius strip... of course...
I present, the world's very first MOBIUS SUDOKU:
Now this sudoku is going to be a ...
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2
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A simple alien safe
Oh no!! Abducted by aliens and put into a labyrinth for ability testing - again!
There is (obviously) no deeper meaning behind this all, but can you help me open this safe, as it undoubtedly contains ...
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Two chunky pixelated X's locked in mortal combat!
In this dramatic image, we witness two rather chunky pixelated letter X's (having recently fattened themselves up for the approaching winter) locked in mortal combat, fighting to the death for the ...
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A hungry ant on a matchbox
A hungry ant is standing on the top of an empty matchbox cover (without its drawer) and has detected the smell of a drop of honey on the floor of the cover as shown in the figure below. What is the ...
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You go wherever you go today
A conclusion to my entries in the Fortnightly Topic Challenge #32: Grid Deduction Hybrids. This metapuzzle incorporates the three previous puzzles in this series:
Desert Irrigation Project
I am an ...
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4
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How do I arrange pencils so they all touch each other?
How do you arrange 6 pencils so that each one touches the other five? And what about 7 or 8?
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Stonehenge - the true purpose
During the last year I've been working on solving the mystery behind these funny stones in Wiltshire, England. Now I'd like to have you join in on the fun and hope you enjoy discovering the true ...
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A Slightly Moth-Eaten Integral Sign
The following slightly moth-eaten integral sign:
... can be folded onto the surface of a cube in a way that perfectly covers the entire cube with no gaps and no overlaps.
How can it be done?
(You ...
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1
answer
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How can this fractal shape perfectly cover a certain platonic solid?
The following fractal shape has a surprising property:
This two-dimensional shape can be folded onto the surface of a regular polyhedron (one of the five platonic solids) in a way that perfectly ...
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Wrap a squashed, bullet-riddled lowercase lambda around a cube
The following rather squashed and bullet-riddled lowercase lambda:
...can be wrapped onto the surface of a cube in a way that perfectly covers the entire cube, with no gaps and no overlaps.
How can ...
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4
answers
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Martin Gardner's "The Twiddled Bolts"
This is a puzzle of Martin Gardner, taken verbatim from My Best Mathematical and Logic Puzzles:
Two identical bolts are placed together so their grooves intermesh. If you move the bolts around each ...
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1
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3D nonogram, beginner's edition
Trying out the concept of 3D nonograms. This one should be pretty simple.
Name the depicted object.
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These alien safes have no end
Well, I could solve the last safe, but what did it buy me? Just another instant-teleport and boom... here I am again!
In a single room with very few things around me, most notably a safe, and no door ...
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Measuring Water with a Holey Cube
You have been given a transparent glass cube, which has a small hole at the center of one of the faces. How can you fill the cube with water occupying exactly one third of its volume?
Edit: The ...
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Isometric Heyacrazy - Now In 3D!
This is a Heyacrazy puzzle on an isometric grid.
Rules of Heyacrazy:
Shade some cells of the grid.
Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected.
When ...
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19
votes
3
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Arranging cubes
You are asked to arrange 42 identical cubes such that exactly three of each cube's faces completely overlap another cube's face each.
Is this task possible? If not, why not?
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Maximal-volume cube net from unit square paper
Given a square piece of paper (say 1x1), what is the largest cube net you can cut out of it?
('largest' meaning with maximal volume; 'net' meaning it's possible to fold into a cube (somehow))
This ...
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Can you cover a cube with copies of this shape?
The following shape has an interesting property:
It is possible to map multiple copies of
this shape onto the surface of a cube in a way that perfectly covers the entire cube with no gaps and no ...
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Wooden Snake Puzzle
I have a wooden snake puzzle in my collection that has been unsolved for years. I wondered if any of you might be interested. I have fiddled with it, but think it might need dynamic programming or ...
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3D cryptic brain melter
An entry in Fortnightly Topic Challenge #43: Variety Crossword Grids
This is a three-dimensional cryptic crossword. The seven squares in the picture depict the layers of a 7x7x7 cube. The "away&...
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3D Masyu - A Die
Fold this net into a cube and solve this 3D Masyu.
The original Masyu rules apply. In addition, question mark '?' should be replaced by either a black or white circle.
Side note: Yeah, it's almost a ...
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Wrapping a Galaxy Around a Cube
The following galaxy-like shape:
can be folded onto the surface of a cube in a way that perfectly covers the entire cube with no gaps and no overlaps.
How can it be done?
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votes
1
answer
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Cover a cube with four-legged walky-squares!
This is a four-legged walky-square:
This shape has an interesting property: It is possible to map multiple copies of this shape onto the surface of a cube in a way that perfectly covers the entire ...
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3D nonogram – Name the object
This is a 3D nonogram. The first five boxes represent the five layers of a $5\times5\times5$ cube, and the last box shows the enumerations for the Z-axis. (Note that 11 means two stretches of length ...
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A cube build with cuboids
You are given 27 pieces of 1x2x4 cuboids. Is it possible to build a 6x6x6 cube using those 27 cuboids?
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3D cryptic featuring Mao, Stalin and Simba's uncle
This is a three-dimensional cryptic crossword. The eleven squares above represent the layers of a $11\times11\times11$ cube.
Across
21. Tribunal's way to imprison you in the old days (10)
25. Sir ...
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Color the cubes, then assemble them to form a larger cube
Goal: Paint 27 cubes using three colors (for example, red, yellow, and blue), so that you can form a 3x3x3 cube with all surfaces in red (for example), a 3x3x3 cube all in yellow, and a 3x3x3 cube all ...
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Cover a single cube with FIVE identical cube nets
Start with five identical cubes:
Your challenge:
Cut and unwrap all five cubes into five identical cube nets.
Show how to re-fold these five cube nets to form the surface of a single larger cube, ...
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3D nonogram – What's in the box?
This is a three-dimensional nonogram. The first six squares depict the layers of a $6\times6\times6$ cube. The final square gives the enumerations for the Z-axis, top to bottom. Some rules:
The grid ...
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A cubeful of three-dimensional devilry
This is a three-dimensional cryptic crossword. The seven squares represent the layers of a $7\times7\times7$ cube. The clues are a mix of Printer's Devilry and normal cryptic clues.
Across
13. While ...
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1
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Is this 3d Sudoku possible?
I was looking at images of 3d Sudoku's on Bing, because I was looking for a $9\times9\times9$ Sudoku, where each horizontal, vertical left-right and vertical top-bottom plane was also a Sudoku.
...
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Fair n-sided dice
I have recently bought a fair $10$-sided dice for generating equally distributed random numbers from the range $1,2,\ldots,10$. Let me describe this dice in some more detail. Consider a regular 5-gon $...
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Puzzle about 6 infinite cylinders in space
You have 6 infinitely long cylinders (tubes) with the same radius R. Can you arrange them in space in a way that every cylinder touches the other 5? By touching, I mean have a common point or a line. ...
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Turn two cubes into one!
Here are two identical cubes:
Your challenge:
Start with two cubes of exactly the same size.
Cut the surface of each of these two cubes along its edges and unfold the surface into a 2D shape. (So ...
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Flood on the top floor
There has been a water incident on the top floor of a building, and one apartment has suffered some water damage. As in, a lot of water damage. The entire apartment is filled waist deep with ...
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3D Crossword, Cryptic, Statue View & Maze
The following image depicts the layers of a $5\times5\times5$ cube. Using 3-dimensional thinking, can you find the way out of the cube?
Empty version with no crossword numbers
Empty version ...
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3D nonogram – What's going on?
This is a three-dimensional nonogram. The first six squares depict the layers of a $6\times6\times6$ cube. The final square gives the enumerations for the Z-axis, top to bottom. Some rules:
The grid ...
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1
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Rhombicosidodecahedron Slitherlink
This is a Slitherlink puzzle, being played on the surface of a 3D object, a Rhombicosidodecahedron. If you are not familiar with Slitherlink puzzles, I don't suggest starting on this one.
Rules in ...
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Tri-bladed Boomerang vs. Octahedron!
The following tri-bladed boomerang shape:
... can be folded onto the surface of an octahedron in a way that perfectly covers the entire octahedron with no gaps and no overlaps.
How can it be done?
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Masyu keep making those 3D puzzles?
This is a three-dimensional Masyu puzzle. The five squares depict the layers of a $5\times5\times5$ cube. The goal is to make a single loop in 3D space which fulfills the following properties:
The ...
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