Questions tagged [no-computers]
A puzzle designed to be solved without using calculators, online decoders or computer programming.
90
questions
19
votes
5answers
681 views
Square Spin #1: Sun and Moon
Defining Square Spin
Lets play a game!
The aim of this game is to transform one image into another using the least amount of moves possible. Here is what a move consists of:
...
14
votes
2answers
313 views
Barrel - Part 5
An entry in Fortnightly Topic Challenge #35: Restricted Title 1. Title based on this xkcd.
This is a continuation of Barrel - Part 1, Barrel - Part 2, Barrel - Part 3, and Barrel - Part 4, but this ...
13
votes
3answers
807 views
Some Stratospherically Strenuous Sudoku
These three sudoku are particularly irksome, can you logically deduce the solutions to all (or any!)
...and provide your reasoning?
They are all proper sudoku - each has a unique solution.
They can, ...
17
votes
2answers
743 views
Color Logic - Find the rule
Find the rule specified in the image below.
Taken from Caterpillar Logic, now the app is gone.
36
votes
1answer
2k views
Riley Riddles in Reverse
In the all-famous Riley riddles, you have to guess one word from clues about its prefix, infix and suffix. Here, instead,
You get three words.
You must find one solution word that you can attach.....
12
votes
2answers
1k views
Alphabetical Sudoku
Who loves fish?
Okay that might sound a bit weird but don't worry, I am still sane.
Maybe.
To answer the question you must complete the Sudoku below. A word will appear in the highlighted box which ...
15
votes
3answers
358 views
Some-what-not-with-standing word connections
What words can fill the boxes?
Each pair of linked words forms an uncapitalized unhyphenated word
when joined end-to-start according to their left-to-right or top-to-bottom
order in the link.
...
7
votes
2answers
273 views
Square Spin #2: Climb the Mountain!
Square Spin History: #1>#2
New Rules
This puzzle introduces two new square types:
Unmovable squares (Un)
Replaceable squares (Re)
Plus the concept of ambiguity!
...
7
votes
2answers
314 views
Desert Wanderings bring…Ciphers? Part 2
Part 1 can be found here
Part 3 can be found here
As you utter your answer, along with its reasoning of course, the Sphinx clearly looks disappointed.
You are unfortunately… Correct. Clearly I made ...
16
votes
9answers
4k views
Solitaire Chess
A friend of mine got me Solitaire Chess for Christmas years ago. I set up the board below. Is it possible to solve it? If so, what is the solution? (No programs allowed- Use only your brain.)
Rules:
...
15
votes
9answers
4k views
Perfect Squares!
A question was asked in a mental ability test yesterday.
Write four distinct numbers with these properties:
1. Sum of each pair is a perfect square.
2. Sum of all four is also a perfect ...
14
votes
3answers
1k views
10
votes
2answers
6k views
Find the 4-digit code!
An agent has created a 4 digit code from the result of a maths equation involving all the digits 1-9. We know where the number 3 appears in the multiplication, but not any of the other 8 digits.
<...
13
votes
3answers
1k views
Crossword gone overboard
This puzzle is part 24 of Gladys' journey across the globe. Each part can be solved independently. Nevertheless, if you are new to the series, feel free to start at the beginning: Introducing Gladys.
...
6
votes
1answer
1k views
Encoding Morse Code
The letters of a message are converted to Morse code, with a space between each pair of letters and two spaces between each pair of words. Each pair of elements (for example dot-space, dash-dash, and ...
19
votes
2answers
1k views
Self-intro to mo-Roman numerals
Here come mo -Roman numerals — just like
Roman
numerals,
only mo’ so.
(Explained as we go.)
What number can spell itself in two different ways
...
10
votes
2answers
308 views
How to fill a honeymoon
How can a honeybee visit all cells
exactly once in this crescent shaped honeycomb,
beginning at the bottom tip and ending at the top?
The starting cell, at ...
7
votes
2answers
870 views
Triangle with incircle [closed]
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 ...
10
votes
2answers
3k views
How many Strobogrammatic numbers are there from 0 to 99999
0,1,2,5,8,11,69,96 are Strobogrammatic numbers.
We call a Strobogrammatic numbers if:
When it is typed on a calculator, and the calculator is spun 180 degrees, the number visually looks the ...
9
votes
2answers
273 views
Word connection squares!
This puzzle is in the spirit of Word connections, but is a more elaborate version of the same idea.
In each puzzle, you have a square of seven words of the following form:
...
4
votes
4answers
385 views
Word connections
I am trying a new kind of puzzle so feel free to leave constructive comments and opinions! Thank you!
The objective of this puzzle is to connect 2 words by using a chain of words that connects each ...
2
votes
2answers
95 views
Tiling rectangles with Hexomino plus rectangle #2
Inspired by Polyomino T hexomino and rectangle packing into rectangle
See also series Tiling rectangles with F pentomino plus rectangles and Tiling rectangles with Hexomino plus rectangle #1
...
1
vote
2answers
157 views
Tiling rectangles with Heptomino plus rectangle #7
Inspired by Polyomino T hexomino and rectangle packing into rectangle
See also series Tiling rectangles with F pentomino plus rectangles and Tiling rectangles with Hexomino plus rectangle #1
...
29
votes
1answer
2k views
A Secret Job . . . but what is it?
Mr. Peters, a freelance muscle-for-hire sort of fellow, had been manning his desk for days now waiting for something to do when at last the phone rang. A job! The nerdy sounding person on the other ...
47
votes
1answer
1k views
re-re-reCAPTCHA
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 ...
43
votes
2answers
2k views
24
votes
5answers
2k views
Superhero words!
Quietly walking among us are words which are actually superheroes in disguise! Just as Diana Prince spins around to become Wonder Woman, some seemingly ordinary words can spin around to reveal their ...
47
votes
2answers
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 ...
46
votes
2answers
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 ...
28
votes
3answers
3k views
Uh oh, the propeller fell off
I was rummaging through a trunk in the attic when I found this vintage game. It is some sort of pinwheel or propeller mounted on a board. The propeller has a cryptic series of letters painted on it, ...
16
votes
1answer
563 views
Riley Riddles in Reverse, batch 2
"post some more sometime :)" -- user @Dragonrage in the comments of Riley Riddles in Reverse
Here's another batch of "inverted" Riley riddles. These still work exactly like the ones before:
You ...
30
votes
1answer
2k views
Computation without a computer
In the number $(1+\sqrt{3})^{2015}$, what is the 224th digit after the decimal point?
You may NOT use a calculator, computer, or any electronic aid to answer this question. Only pen(cil), paper, and ...
18
votes
7answers
2k views
Fully-Firstable Anagram Sets
Okay, first let's define some terminology:
Anagram - Oh come on, how are you on Puzzling.SE if you don't know this one?
Anagram Set - a list of words that are all anagrams of eachother, e.g.:
ACTS
...
17
votes
1answer
1k views
The Lord of the Puzzles
In 1904 (at the age of 12) J.R.R. Tolkien sent a "puzzle letter" (pictured below) to a family friend; Father Francis Morgan.
What does it say?
Obviously it would be trivially simple to google the ...
7
votes
1answer
545 views
Don't bully your little sister at chess
This puzzle was inspired by @RewanDemontay's puzzle De-zephyr The Solution!. Rewan kindly granted me permission for making this puzzle and citing his as my source of inspiration. I thought of naming ...
40
votes
4answers
3k views
Five Slitherlinks
Solve five Slitherlinks, each with a unique solution.
Please say a word regarding (or show an image depicting) each solution method.
30
votes
2answers
2k views
Parallelisation
An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids
Puzzlers, I am presenting a set of six duo-grids! Of course, I need to tell you how they work - you are given a grid. Looking at it,...
20
votes
1answer
1k views
Farmer needs to get his word across the river
In the spirit of the classic river-crossing puzzles:
...
19
votes
2answers
721 views
Step into the Octagram
The diagram below shows a partially-filled "octagram". Step into it, if you dare!
At every vertex in a long word.
Flowing into every vertex are two short words. Anagrammed together, these two short ...
18
votes
2answers
1k views
Three for the price of one
While browsing through your local puzzle store, you see something you can't resist: a box which promises two grid deduction puzzles for the price of one!
The vendor explains that the box contains a ...
16
votes
5answers
2k views
Divisible by seventeen
Determine the smallest integer $n \geq 0$ for which
the decimal digit sum of n is a multiple of 17
the decimal digit sum of $n+1$ is a multiple of 17.
No computers! The puzzle has a nice direct ...
14
votes
1answer
393 views
The road to El Dorado reconstructed from fragmented accounts
You are seeking the route to the lost city of El Dorado. You have assembled several historical accounts from explorers who claim to have reached it. Unfortunately, the accounts are incomplete, ...
11
votes
7answers
1k views
Fill in the boxes to get the right equation
Here is a math puzzle I had a little bit of hard time with
No computers please
There is a solution without inverting 6 to 9
10
votes
1answer
539 views
Oriental House: An original grid-deduction challenge
A different approach to an old concept of mine, Oriental House is a new grid-deduction puzzle based once again off exits and entries.
The rules are as follows: Draw a path from S to F, passing ...
8
votes
1answer
169 views
Uh oh, now the boards are missing!
I found another trunk in the attic, with more of those vintage propeller games. This time, I've got propellers, but no boards.
Is it possible to figure out the whole board from just the propeller?
...
6
votes
3answers
469 views
Calculator Bomb
So, I need your help.
I got home after a long day and found a calculator roughly taped to my door. However, there was something much more disturbing attached to that calculator. It was some kind of ...
23
votes
7answers
3k views
Like totally amazing interchangeable sister outfit accessory swapping or whatever
OMG, me and my sister are like total BFFs and we share clothes like all the time! We soooo have the same sense of style and we borrow stuff from each other like every single second!
We don't even ...
17
votes
3answers
3k views
Prime to Prime: Get all first 25 Prime Numbers using up to 4 Primes
The first 25 Prime Numbers are
2,3,5,7,11,13,17,19,23,29,31,37,41,43,47,53,59,61,67,71,73,79,83,89,97
Using up to 4 prime numbers and the following mathematical operations, get all the 25 primes.
...
15
votes
4answers
401 views
E's-y Word-Square Fill-in
Not necessarily easy, but "'E's-y"!
For each word square below, the Es have been filled in for you. Your task is to complete the rest of the square using only ...
14
votes
2answers
385 views
A series of fortunate transpositions
Using only a sequence of transpositions, see if you can take this:
to this:
while maintaining English words on each of the three horizontals.
At each step, you may transpose any two neighboring ...
