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6 views

Wormeus and the Stickotaur (maze 3)

This is the third maze in the Wormeus series. Previous puzzles are here and here This shouldn’t be too difficult but contains a cute gimmick that isn’t possible in the original Theseus mazes sans the ...
10 views

Fetching Alchemist II

This is a puzzle from the Expert section of my game Fetching Alchemist, visually modified for presentation here. It is a variant of the Travelling Salesman problem where you are trying to complete a ...
24 views

Another puzzle with area

Squares $ABCD, DCGH, BEFG$ and $ELKM$ are positioned as shown on the picture. Find the area of triangle $DGK$ if you know that the area of square $ABCD$ is $20$.
22 views

Puzzle with the point inside paralelogram and area

We have a paralelogram $ABCD$ and point $P$ inside it. Halflines $BP$ and $DP$ cuts respectively lines $AD$ and $AB$ at $E$ and $F$. Why are the area of $ABPD$ and $CEPF$ the same regardles of the ...
30 views

How to solve this equation

$${2\over x-14}+ {5\over x-11} = {5\over x-13}+ {2\over x-9}$$ It is puzzling me for a days. I'm getting huge polynomial I don't like.
104 views

Adding coins inside a ring of coins

17 identical coins with diameter 1 are lying flat on a table, such that their midpoints build the vertices of a regular 17-gon (regular heptadecagon) and adjacent coins touch each other. What is the ...
114 views

What begins with letter T and ends with letter T, use after death? [closed]

What begins with letter T and ends with letter T, use after death?
32 views

How many times they should journey? [closed]

In a Colony, there are men, women and children. 4 women can carry as much as water as 7 children. 3 men can carry as much as 2 women and 1 child combined. If 7 men, 15 women and 4 children each visit ...
78 views

Fetching Alchemist I

This is a puzzle from the Expert section of my game Fetching Alchemist, visually modified for presentation here. It is a variant of the Travelling Salesman problem where you are trying to complete a ...
52 views

What's the encrypted code?

What is the code in: ...
592 views

Who will win in a game of writing 3 consecutive Xs on a 2022 × 1 board?

Ana and Bob alternately write Xs on a 2022 × 1 board. The winner is the one who makes 3 consecutive Xs. Who has the winning strategy if Ana plays the first move? Describe such a strategy.
43 views

Peg Solitaire variant: from 48 on an 8x8 board

Looking at David Ahl's Basic Computer Games, one of the programs that caught my eye was One Check. It's like Peg Solitaire, which I've figured, but it's on an 8x8 board with the 4x4 inner bit hollowed ...
79 views

Snake game on a 9×9 grid

You are playing a snake game. The snake starts in the top-left corner of a grid. Each cell of the grid is either empty or a wall. Each turn you can press a key to move the snake in one of four ...
93 views

You've been caught, sweetie

I sent six puzzles to the Times but received the following reply: Dear Sir, We are sorry to reject your crossword submissions for the following reasons: Squares must be 15x15 or 21x21 Words cannot ...
70 views

Snake game on a 6×6 grid

You are playing a snake game. The snake starts in the top-left corner of a grid. Each cell of the grid is either empty or a wall. Each turn you can press a key to move the snake in one of four ...
88 views

Can you find and capture a shapeshifter?

A town was invaded by aliens, and some of its residents were kidnapped and replaced by shapeshifters. You're tasked with capturing one of the shapeshifters. Here's the setup: There are 7 residents of ...
2k views

Which die should you choose?

You are playing a game with dice. You have a grid with 13 cells shown below. A token starts in the left-most cell (start). Each turn you roll an $n$-sided die and get a number $x$ between $1$ and $n$, ...
42 views

Mathematics based question [duplicate]

Vani meam has three Tatva books, one for chemistry, physics and biology. The chemistry book had 120 pages, the physics book has 10% more pages and the biology book has 10% fewer pages. In a class, she ...
141 views

Finding the root of a basic sequence

The sequence starts with the following: a1 = 1, a2 = 2, a3 = 5, a4 = 4, a5 = 6, a6 = 10, a7 = 9, a8 = 8, a9 = 21, a10 = 12, a11 = 13, a12 = 20, a13 = 33, a14 = 15, a15 = 42, a16 = 16, a17 = 19, a18 = ...
376 views

Windmill: A Masyu Puzzle

The standard Masyu rules apply.
76 views

The shortest puzzle (part 2)

You see a scrawled message on your table: ....................!?.?...?.......?...............?....................?.?.?.?.!!?!.?.?.?!.................!.!!!!!!!!!!!!!!!!!!!!!!!!!!!...........!. ...
77 views

Difficult question .. Plzzzz solve this question [closed]

It's question image plzz answer this question Very difficult question
85 views

1, 2, 16, 4, 16, 16, 52, ?, 52, 16, 52, ?, 40, 52, ? What are these question marks? a) 8, 16, 160 b) 16, 8, 190 c) 52, 16, 160 d) 8, 25, 90 e) Impossible to determine
41 views

Grids with tiles of two colors and connectors

Make a square grid with an even side. Make a continuous trail which passes through all small squares; the trail ends where it started. Where there is an angle you can put a red or a blue tile. On ...
50 views

How to solve the attached sudoku?

Please explain the logic. I am not trying to solve it using trial and error or using any software. I am just looking for the next step. This sudoku is from apple 'Sudoku King' app.
88 views

card(N) != card(N) [closed]

The link below connects to a proof with an error in it. Identify the step(s) where the error occurs, and describe why the step(s) is/are wrong. Proof containing error [1] If there is a bijection ...
157 views

Numbers with minimal sum at the vertices of a cube

The eight vertices of a cube are marked with numbers from 1 to 8 such that the sum of any three numbers on any face is not less than 10. What is the minimum sum of the four numbers on a face?
125 views

One vs many. Can white force a draw?

On an infinite chessboard there's a single white king and N black kings. The nearest black king must be K moves away from the white king. Given N, white dictates the value of (finite) K, then black ...
92 views

Some themed ciphers

You are trying to recognize a theme for your portfolio, but luckily your friend has some themes! ...but encrypted in a cipher. So here are the encrypted lines of text: pi pi pi pi pi pi pi pi pi pi ...
53 views

General aptitude question [duplicate]

Thomas bought a train set with 25 toy engines that run at different speeds. The train set has five parallel tracks that can be built to race the engines. After each round, Thomas notes down the ...
36 views

Rickey Rat puzzle [duplicate]

A powerful sorcerer has hired Rickey Rat as an intern. The wizard gives Rick the task of carrying water from a well to the garden. The path from the well to the garden is up a staircase with 1000 ...
242 views

Can the fugitive escape?

A fugitive is surrounded by N police officers, with the nearest one at distance 1 away. The fugitive and the officers move alternatively. In a fugitive move, the fugitive can travel no more than a ...
64 views

A mysterious list of words [duplicate]

What property do the following words have in common: gnat, green, one, onyx, rail, roof? Can you find another word that has the same property?
135 views

How could I solve the attached Sudoku?

Please explain the logic. I am not trying to solve it using trial and error or using any software. I am just looking for the next step. This sudoku is from apple 'Sudoku King' app.
64 views

A 4x6 grid with adjacent integers with gcd > 1

You are given a 4x6 square grid. Each square of the grid should be filled with different positive integers. The gcd (greatest common divisor) of any two adjacent (horizontally or vertically) squares ...
93 views

Is it possible to calculate group 3's factor of 3 in Thistlethwaite algorithm?

https://www.jaapsch.net/puzzles/thistle.htm I'm trying to generate 29400 ($8C4^2 * 6$) indices for each one of the cube states in G2. $8C4^2$ = 4900 is for solving the corner and edge pieces (forming ...
147 views

The shortest puzzle (part 1)

[![image description here][1]][1] Can't you change everything? I am doing it right now. Question: What is the 1-word answer to this question? Hint:
144 views

Get a expensive donut for 75% off! [closed]

You are going to a donut store, which donuts are more than 500 dollars. The most fancy one is the Donut Dedeluxe, which cost 5000 dollars. Luckily, they have a 75% off which is now 1,250. But, you ...
274 views

Highlights and group dynamics

There are no horizontal word boundaries in the grid. Answers to "across" clues must be written on their correct row, in the order given, with no spaces. Six "down" clues have had ...
487 views

They say, from aperire

The answer to this puzzle consists of 10 letters and is of the form ____ ____ From smallest to largest, row by row Row 1: K.A b. Row 2: W.M b. Row 3: H.S b. Row 4: N.M.B b. Row 5: G.M b.
243 views

Not selling 100 pencils

A shop sells pencils only in boxes of fixed size. It cannot sell 100 pencils. It can sell any larger amount of pencils. It has one of each size box on display. question 1: What is the minimum amount ...
190 views

The infinite country of Saddlestania has some very interesting geography: its elevation from the mathematically flat sea level exactly follows the equation $$\mathbf{z=x^2-y^2}.$$ After traveling ...
67 views

How do I solve the coding decoding puzzle? [closed]

I am able to understand how the first two alphabets,numbers or special characters are working. However I am not able to reach any further a guided help will be most welcome.
118 views

What is the greatest number of pencils that you cannot buy? [duplicate]

A shop sells pencils in boxes of 31 and 38. What’s the highest number of pencils a person cannot buy? In general, if the shop is selling pencils in boxes of p and q, then what is the highest number ...
82 views

“Physical” height of an infinitely distant joint point

When driving along long straight roads, this is what you would typically see: Photo by Luke Stackpoole on Unsplash As you're probably aware, the solid lines on the sides of the road are parallel, in ...
111 views

Chess-based escape room

You go in a room, the door closes. Some sign says: You must find a forced checkmate on the black king in two moves. The key for the Vigenere is ONLY your moves. In other words, if you played Qc3 ...
61 views

How to learn big 3x3 Rubik's cube algsets 1LLL and UF5? [closed]

With more and more people investing time in perfecting algorithms, we always try to go for crazy stuff like ZBLL, OLLCP, full floating 3-style and so on. These algsets are possible to use in actual ...
49 views

What are some specific cognitive gains we can have from blindfold solving a Rubik's Cube? [closed]

I have been blindsolving twisty puzzles since 2013. Blindsolving a Rubik's cube does have an effect on the person's mind. Which mental aspect gets trained more can be used to see if blindsolving does ...