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6 views

Shuffling Magnets

For an experiment, I have to place magnets onto a rectangular board whose dimensions are 3 and 3.5 inches. Between each phase of the experiment, I have to shuffle these magnets around, but if two ...
16 views

The Rock and Roll Connect Wall of Fame

A recent Connect Wall I wrote seemed to attract some interest from newer solvers, so I'm putting together a few of these puzzles to provide a gentler introduction to this puzzle type. EXPERIENCED ...
54 views

Linesweeper (Knight)

Draw a single loop which does not intersect itself by connecting pairs of cells which share an edge. The loop may not pass through any clue cells. Numbers indicate how many of the cells which the clue ...
55 views

My prefix is a human being, My infix is an insect being

My prefix is a human being. My suffix tells you it is what. My infix is an insect being. I have features that can cut.
85 views

Multiplying to reverse digits

Today I noticed that $294$ is a multiple of $49$, which is the last two digits of $294$ reversed. How many other numbers have this property? That is, how many three-digit numbers have a factor which ...
78 views

A Gentle Connect Wall

My last Connect Wall seemed to attract some interest from newer solvers, so I put together this puzzle to provide a gentler introduction to this puzzle type. EXPERIENCED SOLVERS: please let some of ...
141 views

B​ee​p-b​oo​p!​ What's my animal?

Your friend who works at a telemarketing company loves leaving little codes for you all over the place! Today, she left an especially confusing piece of paper taped to your desk! ...
55 views

A dead body was found buried near our Old House?

I lived in a very old house with my father a very long time ago . We are a family with $3$ members , and my mother had died long ago. We have now shifted to a new house , since the old house became ...
105 views

Find the area of the given triangle

Another mathematical puzzle: Find the area of $\triangle FGH$, given that $FG=FH$ and the radii of the circles shown are $2$ and $1$
44 views

What am I dear friends? [duplicate]

I am what that just belongs to you, but only others use it! But you don't get offended nor get enjoyed when others use it. What am I?
153 views

Compoundoku wants REALLY BIG!

Rules of Compoundoku: Solve both left and right Sudokus. In addition, the board below them is the Compound Board of both Sudokus. Each number on the Compound Board should tell either: (1) the number ...
75 views

Numbers with a shared property

The following numbers share same property. What are the next two numbers with same shared property? What are the previous two with the same shared property? What is the largest three digit number with ...
85 views

Say my name. What am I? [closed]

I can be heavy or light. but I have no weight. I can be short or long. but I have no dimensions. I can be sweet or bitter. but I have no taste.
178 views

To be decoded (BINARY)

Look at this image using a pixel editor. Black is 0, white is 1 and red is end of statement
108 views

Final Fantasy $1$ has been released today?

I had a friend in my school who used to hate studies . He always liked to play video games, studying nothing, always talks about video games in school, and also gets some scolds from the teacher. ...
88 views

I am number one, Who am I?

I was bored, so I made another riddle! Enjoy :D I am number one, and number two, and number three, but I will never reach A-level. People pick me up and slam me down a lot. It can hurt sometimes, ...
165 views

Find the ages of mathematician's children

Mathematician: "It was the August of 1997 when they barged into my house..." - Here is his story: Students surprised their mathematics teacher with a cake on his birthday. The teacher was ...
105 views

What's the last line's answer? from this source
767 views

Move just one match

Make a correct equation by just moving one matchstick! This is the source. Spoiler--source reveals answer.
103 views

Jill's flight security woes

Jill is on a flight when she spots her friend a few seats behind her. She tries to get his attention, and is immediately tackled by security. What did Jill do to warrant such a response?
299 views

An interesting,scary and an old riddle

One night I was visiting a friend of mine . I didn't visit him for a long time , though he was a very old friend . We had the following conversation :- Friend :- I am very happy to see you my friend !...
279 views

The Existence of Total False Sudoku

Is it possible to construct a valid $9 \times 9$ puzzle of Total False Sudoku? Total False Sudoku is a regular Sudoku puzzle where all given clue numbers are wrong. A valid puzzle is a puzzle that ...
245 views

Vampires, Insanity and Transylvanian Sisters

This is a puzzle from this site: https://medium.com/i-math/vampires-insanity-transylvanian-sisters-88ce3516fd I thought it was very nice, so I wanted to share it with you. WARNING: the above link ...
145 views

Random sum adds to 1000 [closed]

A random whole number is generated between 1 and 1000 inclusive, and added to a sum. A new randomly generated whole number is generated and added to the sum until the total sum is greater than or ...
1k views

Finding the number of poisoned bottles

This is a well-known problem (discussed here and here), but I am adding a twist to it. A king has 100 bottles of wine and poisons $K$ of them, where $0 \leq K \leq 100$. You have a supply of rats and ...
473 views

Reconstructing points based on the sum of their coordinates version 2

10 points are drawn on a piece of paper with the following rules: Each point has integer coordinates (𝑥,𝑦) that are between 1 and 10 inclusive. For each point there is exactly one other point with ...
192 views

A Connecting Wall off the beaten track!

This is an extended hybrid connect-wall puzzle which fuses components of the most common PSE strain (where group connections also have one final connection, which is the puzzle's answer) with a ...
94 views

Rubik's Revenge: Double Parity

How do I solve this double parity? Can both be solved at once OR need to solve center parity first and then corner parity or vice versa
413 views

Anagram puzzles

5 independent problems in a "self-help arrangement" (which helps you figure out, what the task is, without presenting an example) not left + up = honest tear + boy = jail five + I = kiln ...
116 views

Use me well and I am everybody

One more who/what am I: Use me well and I am everybody, Scratch my back and I am nobody.
65 views

To be gold is to be good

A who-am-I riddle It can be said: To be gold is to be good; To be stone is to be nothing; To be glass is to be fragile; To be cold is to be cruel; Who/what am I?
302 views

Reconstructing points based on the sum of their coordinates

9 points are drawn on a piece of paper with the following rules: Each point has integer coordinates $(x,y)$ that are between 1 and 10 inclusive. For each point there is exactly one other point so ...
167 views

Cryptic Family Reunion: Won't you be my neighbor?

The answer to this puzzle is a list of ten thematically related words or proper names or phrases. Each of these is clued cryptically, and the theme is to be determined. The clues are in a specific ...
157 views

How many ticktocks? [closed]

There's a broken clock. the interval between its two ticks is longer than usual so that it loses 6 minutes an hour. How many ticks should a blind person hear so that he/she be informed of real 6 ...
560 views

Eight campers and the right path

In the spirit of some of my Raymond Smullyan favorites, here's a relatively hard puzzle from a Dennis Shasha collection of $1988$: Eight kids and their guide are lost on a forest exactly one hour ...
871 views

Who broke the window? [closed]

There is a broken window in the house. I asked who broke the window: Gregory: I was not! April : I didn’t do it. August: April was. June : August says the truth Two of them said the truth, and two ...
404 views

A greedy cryptarithm

Find all solutions to $$\begin{array}& & & &E&A&T\\& & &A&T&E\\+&E&A&T&E&N\\\hline&Y&U&M&M&Y\end{array}$$ Where ...
71 views

(This is my original puzzle) Can you work out the number that fills in the question mark? 1,9,216,10000,?
91 views

The Grid World - Catastrophe [closed]

You are a citizen of Grid Land and your job is to keep everyone safe. The Big Flood struck and the sums of each of the coordinates are: [10, 6, 4, 2, 10, 8, 100, 29] and you will have to decode it.(...
3k views

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 ...
74 views

Simple? Substitution Cipher

The following was carved into the cliffs along one shore on the island of Pohnpei after a strange fog had engulfed the island. Even stranger sounds emanated from the fog before it dissipated slightly ...
741 views

Make Riley Riddles, Not War

When a famous man sets out With a frightening weapon in hand In between remain I, devout Against killing making my stand What am I?
401 views

Where is the pilot flying to?

Barry is a pilot for the mafia. Due to his unique cargo, his employers have to give him his destination in code. Everywhere he has flown, from Edmonton to Frankfurt to Atlanta has had an international ...
182 views

My prefix lost a life, My suffix had a meal

My prefix lost a life. My suffix had a meal. My infix has a life. My whole is a big deal. Hint:
78 views

Need help with a online puzzle / riddle [closed]

I found a puzzle on the deep web (http://matrix4ozv2gicar.onion), and I am stuck on access level 2, I am aware someone else posted the same question on the same part as me about a year ago, except it ...
74 views

Two large, one small [closed]

You have two identical circles, with radius 5, on a flat surface standing precisely next to each other(so that the two circles are tangent to each other). Question1: On top of them a smaller circle ...
237 views

Pattern recognition puzzle from reddit

so I've came across this puzzle in reddit r/puzzles, gave it a try and couldn't solve it and it seems like no one else could've either. I tryed reverse search the image and found it on a site called ...
203 views

Trapped and gassed!

“Ouch!” I moaned as I slowly regained consciousness. Someone had knocked me out cold from behind. I now found myself alone, trapped in a small square room. The floor was hard and cold, and the room ...
169 views

Captain Clumsy's crooked 'compass'

Sigh. Captain Clumsy is making my life a misery… again. Recently, I installed a brand-new 'simple' navigation device – one I had invented myself – on his ship. And he clearly didn’t listen to my ...
You are given a tetrahedron $T=ABCD$. Average opposing edges to create a second tetrahedron $T'=A'B'C'D'$ with $\overline{A'B'}=\overline{C'D'}=\frac 1 2[\overline{AB}+\overline{CD}]$ etc. Place $T$ ...