# All Questions

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### What is a Cyclone Phrase™?

If a phrase adheres to a certain rule, then I call it a Cyclone Phrase™. Use the examples below to find the rule. Also find the one error in the chart below. (In other words, one of the phrases below ...
5k views

### Extreme Gerrymandering

It is election season in Puzzlevania. There are two candidates: the incumbent and a challenger. Of the $20$ million citizens, only $1$ percent support the current president; the other $99\%$ favoring ...
2k views

### Help! I can't rock out, with my clock out!

I need your help! Look at this: One, two, one o'clock, three o'clock rock Eight, six, three o'clock, two o'clock rock Nine, seven, one o'clock, seven o'clock rock We're gonna rock around the ...
8k views

### Are you clever enough?

I'm always in your thoughts, technically twice If displayed correctly, just to be precise If you see my left you will call me a con and it would tear me apart if you called me John Take down a note ...
5k views

### A very unique chess puzzle

Find a legal move for white that does NOT mate in one. Source: by Karl Fabel & was reprinted in Martin Gardner's New Mathematical Diversions from Scientific American (pub. Simon & Schuster), ...
3k views

### Ron couldn't quite put his finger on… something?

Ron got up out of his bed, feeling slightly odd. Despite only being conscious for under ten seconds, he felt like something recently slipped his mind, something he couldn't quite put his finger on. ...
4k views

### A Robot's Last Words

There, spread out all over the floor, were the mechanical pieces of a robot. Something had torn it apart, and the debris spanned a radius of a few meters. There was no sign of what might have caused ...
18k views

### One hard IQ question

Can someone explain me the logic behind this? The question is: What comes next in the pattern (out of the 5 possibilities)
7k views

### Famous eater. Who am I?

Although I've never been interviewed, I'm famous all over the world. People love to watch me eat, But some disapprove of my habits. I don't mind working for my food, And I like to eat on the run. ...
269k views

### 6, the magic number

Here's a fun (albeit difficult) one: Make these equations true using arithmetic operations: ...
6k views

### Third, Fourth, Fifth [closed]

A friend of mine made a simple bar bet, in which he wrote down a list of ten words. Turning it around to show me, he covered up the first two words with his hand. The eight words below his hand were ...
6k views

### 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 ...
6k views

### Find the identity of the four troll brothers

The four troll brothers Wudhor, Xhaqan, Yijlob and Zrowag have the following properties: Wudhor always says the truth. Xhaqan always lies. Yijlob lies or says the truth unpredictably. ...
3k views

### What is Lukas Rotter's secret?

The former user Lukas Rotter has had1 an intriguing profile picture: This looks like it's some kind of encrypted message! And just to confirm my suspicions, on his profile he says: By the way, my ...
4k views

### I'm half of a hundred

I'm half of a hundred and both halves of a Belgian detective, two thirds of solar exposure and one eighth of an Age. If you know who I am, post your answer, plus your explanation for each of the ...
5k views

### Locate the hacker

This is my first time making one of these. Hopefully it's not too easy (or too difficult). Let me know what you think. If people enjoy this I will make more! It is May 26th, 2016 After years on the ...
2k views

### A 16 Clue Sudoku Puzzle (but the kings can't be in check)

An entry in the 19th fortnightly challenge... Above is a 9x9 "chess" board with some pieces already laid out, your goal is to fill the board completely, following standard Sudoku rules (i.e. every ...
1k views

Last Friday, I was feeling a bit sad because I hadn't earned much rep recently, so I decided to try this awesome sock puppet thing everyone's been raving about. I logged out of my normal Puzzling ...
1k views

### Self-referential Sudoku

I built this a while back but never had a good forum for it; this seems like the perfect spot to turn it loose. This is a 'traditional' Sudoku; cells are filled with numbers from 1 through 9, and all ...
4k views

### Eight coins for the fair king

You are responsible for creating new types of coins for the court. King respects the forgetful: he wants you to create 8 coins of different value, no more. King respects the feeble: he wants that any ...
4k views

### The vicious wizard…and you!

The vicious wizard Neville has trapped you in the middle of a magical circle of radius $10000$, and you have to find a way out. Every time you want to take a step (of length $1$) in a certain ...
3k views

### My Puzzling Girlfriend

So it's my birthday yesterday and my girlfriend comes over. We're kidding around and I asked her if she'd gotten me something good. She said: "Oh, yeah! Big time!" Well, of course I wanted to know ...
5k views

### Batman and the piano

Batman: Alfred. Are you there? Alfred: Yes, Master Bruce. How may I help you? Batman: ...
34k views

### Grandma likes coffee but not tea

Note: My grandma is a little odd. She only likes certain things. Solve this puzzle by providing phrases that are true. For example: Grandma likes A but not B Grandma likes coffee but not tea. ...
5k views

### The lion and the zebras

The lion plays a deadly game against a group of 100 zebras that takes place in the steppe (= an infinite plane). The lion starts in the origin with coordinates $(0,0)$, while the 100 zebras may ...
3k views

### The Thirteenth Arrow

The mysterious man motioned Walter into a small room. "Here", he said, "is where we test how smart our applicants are." Walter died inside. He had been told that the applications were tough - after ...
3k views

### Just a bunch of dudes

My prefix is dude. My infix is little dude. My suffix is too loud, dude. I'm a stand-up dude.
11k views

### Almost half a million, yet smaller than a hundred [closed]

Consider, for example, the number 420109. It's quite big, isn't it? Not so far from half a million. Yet it can be made to be smaller than a hundred with a very simple trick, without putting any ...
155k views

### 1 2 3 4 5 6 7 8 9 = 100

The sequence of numbers $1\ 2\ 3\ 4\ 5\ 6\ 7\ 8\ 9$ has the property that you can insert mathematical operators in between the numbers from $1$ to $9$ and make the expression evaluate to 100. For ...
16k views

### Puzzle: Who hacked the computer?

I was working my way through some Knight and Knave Puzzles in Discrete Maths by Rosen, when I came across the following question: Four friends have been identified as suspects for an unauthorized ...
9k views

### I am both lock and key - who am I?

Enter! Small or large, as the case may be I'll assist you - it's easy! - I'm both lock and key Who am I?
6k views

### How to make someone open an origami?

I'm offering someone an origami (rabbit shape) with a QR code written inside. This is the beginning of a series of riddles. My question is, how could I make the person I'm offering the origami to ...
4k views

### The SErial Killer (Part 1)

This is part of a series which I'll be continuing if this goes down well enough. If you have any feedback on the puzzle (too hard, too easy, not clear enough, etc) I'd appreciate it so that future ...
7k views

### An untouchable time traveller

I'm needed by a doctor to travel through time, Or a player looking for their keys. When on the plane where the great answer resides, I'm part of the whole Strategy. I can be found in a ...
4k views

### Who's not welcome here?

Five people are discussing their hobbies: "I like baseball", says a man. "I prefer hiking", answers a woman. "I love persian culture", tells a second man. "It's weird, but I like to slice ...
3k views

### Tiling with T-tetrominos in gravity

The goal is to tile all the white squares using T-tetrominos when there is gravity pulling the tetrominos downwards like regular tetris. The black squares are void and the ground is just below the ...
3k views

### Where did Billy go to?

There are lots of happy animals living with me in my house. Yesterday I wanted to enjoy an animal-free afternoon: I looked at Skippy and said "Go to festival". And off he hopped. Then I sent Cookie ...
3k views

### Can you stop the rambling rook?

This is a chess puzzle someone showed me a long time ago. If you already know this puzzle please give the others a chance to solve it first. This puzzle was originally created by Otto Gallischek and ...
15k views

### Does the drunk man fall off the cliff? (a random walk problem)

A drunk man stands with a cliff one step to his left. He takes steps randomly left and right. Each step has probability $p$ of going left and probability $q=1-p$ of going right. Each step is the same ...
7k views

### Why did John buy so many batteries?

World-famous engineer John Johnson decided to take a break from his latest invention, and asked his wife if she had any chores he could do to clear his mind. She handed him a grocery list and told him ...
6k views

### What does this modern art picture represent?

This puzzle belongs to the puzzle series: hyper-modern art Two visitors are standing in front of a painting in the hyper-modern art gallery, discussing it. "Well, I have to admit that I really don't ...
1k views

### A crossword to appease all

(Click for full size) Across 1. Steal extremely experimental metal song or 26-across maybe (6) 4. "Wardrobes malfunctioned", most rang for short interval (8) 10. Future engineer edits New York, USA'...
3k views

### 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" Having ...
2k views

### Japanese Fusion Alphabet Soup

The Dish... ...is an intriguing blend, with a base of classic Western flavours, and a twist of the Orient at its heart. The Ingredients... ...are diverse and are combined in such an unexpected - ...
14k views

### I apologise in advance for this

A man has 17 cigarettes. He gives half of the cigarettes to his oldest son. He gives one third of the cigarettes to his middle son. He gives one ninth of the cigarettes to his youngest son. ...
6k views

### A man possesses a large quantity of stamps

James Joseph Sylvester was one the greatest British mathematicians of the 19th century, who made many fundamental contributions to number theory, combinatorics, and invariant theory. In 1884, he ...
12k views

### I last billions of years or a couple of milliseconds

Please help. I've given this riddle much thought and can't get anywhere. I last billions of years or a couple of milliseconds. I embody the Jurassic period and the Renaissance. I am composed of ...
6k views

### Geography at the pixel level

(enlarged version) The answer is a group of islands.