# All Questions

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502 views

### Three lines through a square

Is it possible to draw 3 straight lines through a square such that they divide it into 7 equal-sized regions?
748 views

### Venn diagram with 7 equal regions

Can you draw 3 overlapping circles (Venn diagram) such that all 7 of the formed regions have the same area? For the case of two circles and 3 equal regions I found this answer: https://math....
134 views

### Thirteen Minesweeper mines that make seven 5s

Can you place thirteen mines on a Minesweeper grid such that they create seven 5s? The size of the grid can be arbitrary. The mines may create numbers other than 5s, but those are irrelevant. A ...
88 views

### Pentagon with sides, diagonals and area that are distinct integers

Can you find a convex pentagon (5 sides) such that all its sides, diagonals and area are distinct integers? Note that a polygon is convex if all its internal angles are smaller than 180 degrees. A ...
220 views

### The music of the heavens

A monastery has a curious practice: they call it the music of the heavens. The monks cycle through a cave with cups, to a stalactite at the center, which drips water. But this is not a steady ...
10k views

### The 100 soldier problem

I saw this problem many years ago. I am sure many puzzlers will know its original name. I was reminded of it when reading about Conquering of Regions problem. A Strategy Game Involving Conquering of ...
230 views

### An Ancient Beauty

My initials are "Y" My initial parts make a ditty sound My first's first is once round My second's middle is blue My whole is blue, too I'm in a pharaoh's gilded mask ...
426 views

### Flying pigs arrive

You’ve built pens for flying pigs. Being, well, flying pigs, they pick their own accommodation in full accordance to their preferences. Can you figure out what creature joined them? Pigs only occupy ...
154 views

### All Aboard the Factorio Train to Far Harad

It’s been a while since you started up your Factorio game and you are trying to remember what you had done with your four trains. Use the clues below to work out which deposit each train is collecting ...
367 views

Forward, I will lead the way. Backward, freedom you shall have. Keep going, I'll hold them back. Take my sword, do what you must. Dead or alive, our rights are just. Who/what am I?
90 views

### Arrange 20 counters and remove 6 form them and not a single square can be indicated?

Arrange 20 counters in the form of a PLUS(+), as you can see in the image. Now, how many different ways are there in which four counters will form a perfect square if considered alone? Thus the four ...
361 views

### Fun time! Guess what I am!

I enjoy a symmetry and my motion is oscillatory From the tip of your hand I spiral down to the end I am graceful and sinuous but to use me is not arduous You probably used me What could I be?
501 views

### Quick Kurodoko Puzzle: Threes and Triples

Kurodoko (taken from Nikoli) Colour cells black according to the following rules. The numbers on the board show the number of white cells from the number to the nearest black cell or to the ...
129 views

### * Playtest feedback request* Puzzle 3

You find the following four images (they are not in any particular order). Your solution is a street name (it will be well known to the players but might not to someone trying the puzzle here).
788 views

### Twelve Minesweeper mines that make twelve 4s

Can you place twelve mines on a Minesweeper grid such that they create twelve 4s? The size of the grid can be arbitrary. The mines may create numbers other than 4s, but those are irrelevant. Good ...
855 views

### Dear Fellow PSE Users,

This puzzle is dedicated to all of you! Instructions There are 8 anagram questions below. In each question, you can rearrange the letters to find an answer, which is 2 English words that describe a ...
390 views

### Quadrilateral with sides, diagonals and area that are distinct integers

Can you find a convex quadrilateral such that all its sides, diagonals and area are distinct integers? Note that a polygon is convex if all its internal angles are smaller than 180 degrees. Good luck!...
129 views

### Help solving Sliding Tiles Puzzle 2x3

So, I'm playing a game (The Da Vinci Code) and are really stuck on a 2x3 tile sliding puzzle. It looks something like this 1 - 5 - 4 2 - x - 3 and it has to look like this: 1 - 4 - 5 2 - 3 - x ...
143 views

### Area of the square

Can you find the area of the following square given the known lengths? Good luck!
181 views

### The Marching Tune

And a one, and a two, and a three four five six! Or a one, and a two, and a three four five! From my home right here, To the end way down there! And then I have a choice Of a one, a two, or a ...
153 views

### First thing, there is always an exception - what am I?

I cast a shadow as dark as I I have been found in a pie Insects sing, in the dead of night Many together is quite the sight What am I? And what does each section of the riddle mean?
174 views

### What is an Infield-Fly Group™?

This is in the spirit of the What is a Word/Phrase™ series started by JLee with Group version puzzles. If a word could be measured with a specific metric, and the result could be separated into ...
2k views

### Minimum number of lines to draw 111 squares

Find the minimum number of lines to draw 111 squares. For example, you can draw a single square using 4 lines i.e 2 vertical and 2 horizontal. Similar, you can draw a 2 square in the grid using 5 ...
185 views

### Who am I? can you recognize me by the given hints?

I am known for the "Worst generation" a part of me known for the naval battle. I am also known for White City. I am the survivor of the Most Dangerous Disease. Who am I? I will add more hints if ...
655 views

### The Google Earth Challenge: “A dangerous flower”

This puzzle is based on Where is it? - The Google Earth Challenge series started by Conifers This puzzle will provide a screenshot in somewhere on Google Earth, please try your best to identify where ...
148 views

617 views

### All numbers twice in a 7x7 Minesweeper grid

Can you place mines on a 7x7 Minesweeper grid such that each number from 0 to 8 appears exactly twice? A similar question about a 5x5 grid: All numbers in a 5x5 Minesweeper grid Good luck!
2k views

### Three knights searching for a princess in a castle

There is a castle with rooms arranged in a 4x4 square grid. The princess living in the castle sleeps in a different room each night, but always one adjacent to the one in which she slept on the ...
5k views

### All numbers in a 5x5 Minesweeper grid

Can you place mines on a 5x5 Minesweeper grid such that each number from 0 to 8 appears exactly once? Good luck!
310 views

### Two knights searching for a princess in a castle

There is a castle with rooms arranged in a 3x3 square grid. The princess living in the castle sleeps in a different room each night, but always one adjacent to the one in which she slept on the ...
292 views

I have big news! I finally have a girlfriend! She's really nice and is studying to be a cartographer. As you know, I don't have much experience with the ladies, so I need some advice. I have been ...
179 views

### Missing lattes and mutually mistrustful words

It's always amusing to watch two kids who don't trust each other swap baseball cards by exchanging them at exactly the same moment. Words can be equally mistrustful about trading their letters. ...
2k views

### Talk about Grandpa's weird talk: Who are these folks?

"These guys are strange" exclaimed Grandpa "Why?" I opened my mouth. Too late. "They constantly talk about only one country and only one sport-- boring sport if you ask me, and, get this, only one ...
79 views

### Variation of Monty Hall problem for gambling on who is the champion soccer team

So let's say, if you can guess who the champion team is for soccer, such as in World Cup, then you win a car. Otherwise, you win a goat. There are 4 teams left. Country A, B, C, and D. And country A ...
3k views

### 6+8=71 move two matches

How can I make this equation true by moving two matches? It's in a game "Smart Puzzles" - it's called Matches, and there are about 13 different games in it. Additional images - my attempts
2k views

### Where is it? - The Google Earth Challenge Ep. 4

Yeh I still can't give out the first hint... Bring it on! :D This puzzle will provide a screenshot in somewhere on Google Earth, please try your best to identify where the location is. The reasons to ...
572 views

### A big cat roams through the middle of this Google Earth hunt

This puzzle is based on Where is it? - The Google Earth Challenge series started by Conifers, :D Note - this puzzle is mostly, if not all, about solving the riddle. I suppose the puzzle could exist ...
229 views

### A Pixelated Sequence - Find the Continuation

A late question inspired by Finger sequence – find the continuation How should the grid above the '10' be coloured?
308 views

### Not Seven This Time - another Google Earth challenge

Where is this? Please don't use Google reverse image search, but solve the puzzle using inspiration and deduction.
152 views

### Attacking queens revisited

Can you place 5 queens on a 11x11 chess board such that they can attack every empty square? It turns out this problem was answered here: http://golovolomka.hobby.ru/books/gik/04.shtml Can you find ...
87 views

### Missing number in the table [closed]

This is my 3x3 grid: $$\begin{matrix} 2 & 6 & 8 \\ 3 & 7 & 3 \\ 6 & 4 & x \end{matrix}$$ Here x should be replaced with some number. Based on the solutions it should be x=1. ...
67 views

### Missing number in a 5x5 table

I'm trying to find a solution for the following puzzle. A friend sent it to me and I know that he didn't create it and that's about it for the original source; I tried to find it on the net but I ...
82 views

### What number should be in the place of “?”

I'm trying to solve this puzzle. Numbers are at triangle, and I have to solve ?-mark: 5 6 1 7 2 5 ? 7 5 Based on solutions it ...
123 views

### Attacking queens

Can you place 3 queens on a 6x6 chess board such that they can attack every square? Good luck!
143 views

### Nurikabe minicubes: the Headache, the Panache, the Apache

These are three-dimensional Nurikabe puzzles. In each case, the four squares represent the layers of a $4\times4\times4$ cube. The goal is to shade some cells in each layer so that the resulting space ...
410 views

### Piece de Resistance - Nine is Three Tripled

Nine is Three Tripled This puzzle is part of the "Piece de Resistance" series. Go back to Part 1 (Ace) for the story.Ace Two Three Four Five Six Seven Eight Nine... Here is the transcription of the ...
858 views

### Seven Places at Once - Another Google Earth Challenge?

This puzzle is based on Where is it? - The Google Earth Challenge series started by Conifers, :D As usual, no reverse image are allowed. Hey, check these out! These seven places are so special ...
275 views

### Thirsty men problem [closed]

Currently, I am modeling a problem that I am working on (in distributed systems) as a riddle and I'd like to know your opinions, suggestions and solutions. You can find it here on github. Thirsty men ...