# All Questions

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78 views

### Universal bisectors

A bisector is something that cuts some other thing into two equal pieces. More concretely, assume we are given a reasonably well-behaved (for example, compact) 3D object and we are looking for planes ...
194 views

### The Perplhexing Mystery

There has been a jailbreak in my (imaginary) town. And I, a Junior Detective of the town, have gone to investigate this. As I reach the police station, an inspector comes out to greet me. No doubt he ...
89 views

### Guineas Dealer ||||||||

This visionary turns into a comedian, an animal and a fictional hero around Christmas. What is his favorite machine? Note: The lines after the word "Dealer" in the title have nothing to do ...
73 views

### A Surprising Riley Riddle

My infix is a potato reporter, My suffix is a garden storer, My prefix is Martin's significant other, My whole will make you bowled over. What am I?
66 views

### Bisecting a 3D object into two equal volume objects - 2

Given the following 3D object and means of an unmarked ruler to draw lines on its surface define a straight cut that will split it into two objects with the same volume. Hint: It seems to have at ...
205 views

### Statement: [infix] will [whole] [suffix] [prefix] [infix] will

[infix] will [whole] [suffix] [prefix] [infix] will. The above, when the gaps are filled, will be a reasonable statement. What are the two infixes?
154 views

### Primes and squares in a grid

i) Place thirteen different three-digit prime numbers in the empty cells of this grid. ii) Now place thirteen different three-digit square numbers in the empty cells of this grid. How many solutions ...
79 views

### Relations between numbers taken three at a time [closed]

Let's have the following numbers. $(5i+\frac{1}{2})$, $(2i+3)$, $(\frac{-101}{8})$, $(7i+4)$, $(5i+1)$, $\frac{(40i-97)}{8}$. How are these numbers related when taken three at a time? Operations ...
113 views

### When is the full moon?

During each lunar cycle, the full moon is technically full for one instant, but to the human observer, the moon appears full for 2-3 days and nights in a row, making it hard to tell on which date and ...
1k views

### Find three ways of forming the number 100 using 3,3,5,7

As it says in the title. Rules: anything not explicitly allowed is forbidden. use 3, 3, 5, 7 and multiplication, division, sum, difference, unary minus, and exponentiation in any order. Parentheses ...
103 views

### Crack the code: csdsgsdsfgsfsfcsdsgsgs

My friend gave me this code which they say is basic. Can you help me? csdsgsdsfgsfsfcsdsgsgs That is the code, can any of you solve it?
59 views

### Unusual Vowelburgers™

Inspired by Avi's Vowelburger™ Riddle and the variations thereof I got these Vowelburgers™ on discount, and they have a little different mouthfeel than others. Why is that? Patty Vowelburger™ A Ink ...
150 views

### Three white queens, two white knights, and one rook on a chess board

On an 8 x 8 chessboard, place three white queens, two white knights, and one white rook so that every cell of the board is under attack by at least one piece not standing on it. Source: https://www....
237 views
+100

### A new adventure awaits! Let's go!

A tale is being told here, one that spans many years and generations... but what kind of tale might it be? Pastebin link to a transcript of the clues, including colorblind assistance. Note that Y = ...
81 views

50 views

### What's at my back?

I always have something on my back whenever I use my PC and I have some definitons to figure out what it is. financial institution that accepts deposits from the public a family of large marine ...
152 views

### When is the final telephone post installed? [closed]

The puzzle is as follows: The Philadelphia telephone company will install 35 telephone poles along Broad Street. Each post must be located at equal distances from each other. It is known that the ...
99 views

### I invited them and no one came

My colleague told me this morning with frustration: To 200 friends I sent invitations to my birthday party, and not one person came. The last paragraph of the invitation had a mysterious sentence ...
73 views

### Number of turns for two wheels to bring edge-points together

The puzzle is as follows: We present you below this riddle. A certain mechanism opens a gate of a maximum security lab. It just happens that a glass lets you see the mechanism and you know the ...
114 views

### I need some help with this 15x15 nonogram

I have been working on this nonogram for some time and can't seen to figure out what to do next... This is the link: https://nonograms-katana.com/play/#game
70 views

### Can anyone think of more examples of pair of words like “Mindful” and “Mind full”? Both sound same and have different/opposite meanings [closed]

I am looking for pair of words or using multiple words which sounds similar but have different/opposite meanings(like an example mentioned in the question above). I posted this question in English....
280 views

### The Alan Parrish question

Two stereotypical british gentlemen that don't know each other engage in this unusual conversation (it's almost as if they were a setup for a puzzle): Gentleman A - Hello sir, I'll have you know that ...
222 views

### The Green Periodic Puzzle

This puzzle follows from the Purple Periodic Puzzle (these puzzles are solved individually). Another strange periodic table has appeared and it's hiding a secret word. Can you find out what's strange ...
58 views

### Fair and square island hopping [duplicate]

If amateur fiction is not your thing skip to the bottom. As IP (Implausible Physics) expert for DREAM, the Department for Reckless Engineering and Advanced Megalomania you have been tasked by sheikh ...
560 views

### Calculation - the hard way

This is a puzzle I love to play with my math students and I hope you will enjoy it too: You are given the numbers 1, 2, 3, 4, and 5 exactly once. Your target is a number, e.g. 36. Can you create a ...
187 views
+100

### A Peculiar Find-A-Word

I was solving a crossword in my local newspaper when I came across a clue that made no sense: 19 Across: Be inappropriate On the face of it, there is nothing odd with this clue until I realised: 19 ...
2k views

### 28 Minutes Later

An entry in Fortnightly Topic Challenge #50: Escape Rooms I open my eyes to find myself lying in a bed in a white room. Sitting up is difficult, as a tangle of wires and tubes are attached to my arms ...
189 views

### Peas at the barbecue saved the day!

You were at your neighborhood barbeque when noticed a lady reporting a theft to the police. This is what you heard: Lady: Help! A man grabbed my purse and ran away! Police: Did you notice anything ...
494 views

### The Purple Periodic Puzzle

Below is a periodic table that's hiding a secret word. Can you find out what's strange about this purple periodic table and find the answer. Text-only version: ...
43 views

### How to find a zip file as large as possible [closed]

How one can find a text file with 1000 bytes which zip file is as large as possible? I think it must be over 1000 bytes.
62 views

### Finding the hypotenuse of a right angle triangle when one side has been given [closed]

If one side of a right angle triangle has length equal to $a^{n-1}$, where $n\ge2$ and $a$ is any odd number greater than 1, how do we find the length of the hypotenuse? The lengths of the sides of ...
49 views

### Decrypting a block cipher puzzle from a hex string [closed]

I have the following hex-string puzzle: ...
2k views

### How many matchsticks need to be removed so there are no equilateral triangles?

The puzzle is as follows [with minor copy edits for grammar]: By only using matchsticks of equal length a set of equilateral triangles has been built as indicated in the figure from below. With that ...
213 views

### How to get the least possible sum in a closed loop set of squares?

The puzzle is as follows: The figure from below represents a set of 12 squares joined forming a closed loop. By using only the numbers from 1 to 12 fill in the blanks. The condition is that, without ...
141 views

### How many lines are needed to connect all smiling toasters in a 4x4 grid?

The puzzle is as follows: How many straight lines do you need to draw the least possible to join all the smiling toasters if you should not raise the pen or go over any line already drawn? Remember ...
317 views

### Two knight tours on a 4x4 grid

Two knights are placed on opposite corners of a 4x4 grid. Can you move* each knight 7 times, such that each cell of the grid is visited exactly once by exactly one of the knights? *Note that a knight ...
221 views

### Minimize the longest King chain on a 6x6 ternary grid

This puzzle is an extension of this one: Minimize the longest King chain on a 5x5 binary board Given a grid filled with numbers, we define a King chain to be a path on the grid such that: The path ...
118 views

### Minimize the longest King chain on a 7x7 binary grid

This puzzle is an extension of this one: Minimize the longest King chain on a 5x5 binary board Given a grid filled with numbers, we define a King chain to be a path on the grid such that: The path ...
406 views

### Sometimes with Feathers?

When in red, I was very loud. In high definition, a treasure. You put me in to interfere. Rest on me for your leisure. Put me between the last two letters, I am an Asian plant. Keep some of me in the ...
60 views

### intercepting the box [duplicate]

If you need to send a message in a box to a person so that no one can intercept it and get the message, how do you do so if you have a padlock and key and they have a padlock and key
81 views

### Vowelburger™ Inside-Out Burger

Inspired by Avi's Vowelburger™ Riddle here and Ébe Isaac's Double Supreme Riddle. The local Vowelburgers™ has added a new item to their ever-expanding menu, the Inside-Out Burger! This peculiar ...
185 views

### Choosing squares on a square board [closed]

I have an $8 \times 8$ board. On the board, I want to choose 2 unit squares in each column and row such that none of the chosen squares are touching. This means they cannot share a side or a corner. ...
230 views

### An Evil Cartesian Psycho

I came up with this puzzle when I was in high school. There is an island owned by an evil man who keeps some tourists who were visiting the island a few years ago captive. The authorities demanded ...
951 views

### Working as a Family

Within this Boggle grid are the names of the members of a family. The unused letters will reveal the name of the original head honcho. ...
131 views

### Chess - I will eat!

Suppose that you are playing White, and your aim is to eat a black piece (pawns qualitfy) in the fewest moves as possible and Black are not cooperating at all, and, even more, Black's aim is to ...
2k views

### A Math Riddle: But the math does not add up

Grandpa had a lot of different books of stamps on his desk. He was counting them. I was curious. “What are all those stamps Grandpa?” “I just got back from the Post Office son and bought a bunch of ...
197 views

### These words have the same properties, but how?

Asparagus, Man, Erode, Aerodynamic, Innards, Bins Mine, Rob, Fort, Hexagon, Tera, Nights Flashbacks, Lost, Mono, Grand, Dystopia, Focus Splashdown, Troupe, Karate, Duel, Catchy, Contact Acrobat, ...
229 views

### All possible locations of a robot going from $(x,y)$ to $(x+y, y)$ or $(x,x+y)$ [closed]

Suppose I had a little robot on the coordinate grid that moves according to the following rule. If it's at the point $(x,y)$, it can move to either $(x+y,y)$ or $(x,x+y)$. If the robot starts at the ...