Questions tagged [no-computers]
A puzzle designed to be solved without using calculators, online decoders, or computer programming. Using a computer to type and post the answer is allowed; the spirit of this tag is to make people solve the puzzle on their own.
798
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Ended up with 'empathise'
I started off with a one-letter English language word. For every step, I added one letter of my choice, and re-arranged the letters to make a new word. By the end, I had:
EMPATHISE
What was the word ...
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0
votes
1
answer
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Minimum function optimization puzzle #4: Using negative numbers?
Previous puzzle
Take this puzzle of mine that I created around a week ago:
Take these 3 functions: $f(x):=x+8,g(x):=x^2-3,h(x):=\sqrt x$
Starting from $x=0$,$$\color{black}{\text{How many times will ...
- 1,185
0
votes
2
answers
132
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Minimum function optimization puzzle #3: 3 functions
Previous puzzle
Take this puzzle of mine I created recently:
Let $f(x)=x+1$, $g(x)=x^2-1$, $h(x)=2x-4$. Starting with $x=0$ and applying these functions as needed, what is the minimum amount of times ...
- 1,185
1
vote
1
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113
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A Hidato, but with no given numbers?
I can be a bit evil sometimes. Today, I am going to give you a Hidato with no numbers! It gets worse: This puzzle is on a Mobius Strip Y[1] However, I will give hints as to what the numbers are, so ...
- 1,185
0
votes
2
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108
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Minimum function optimization puzzle #2
Previous puzzle
Take this puzzle of mine I created about an hour ago
Take two functions, $f(x):=x^2$ and $g(x):=x-3$. Starting from $x=0$ and applying these functions as needed, what is the minimum ...
- 1,185
1
vote
1
answer
167
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Is my solution to a mathematics puzzle I created the most efficient solution there is to it?
Here's a puzzle of mine that I created around 2 hours ago:
Let $f(x):=x^2$ and $g(x):=x-4$. Starting with x=0, what is the least amount of times you need to apply the functions $f$ and $g$ so that at ...
- 1,185
9
votes
1
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A Hidato, but with a complex twist!
Today's Hidato puzzle has a pretty complex twist. What is the twist, you ask?
This is what the twist is:
There are three different colors:
Yellow: Represents a prime number
Green: Represents a ...
- 1,185
8
votes
1
answer
355
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Shuffled binary numbers version 2
Here are 0 to 15 in binary:
0 1 10 11 100 101 110 111 1000 1001 1010 1011 1100 1101 1110 1111
I have shuffled and concatenated them to obtain the following strings:...
- 33.2k
6
votes
2
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734
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Shuffled binary numbers
Here are 0 to 15 in binary:
0 1 10 11 100 101 110 111 1000 1001 1010 1011 1100 1101 1110 1111
I have shuffled and concatenated them to obtain this string:
...
- 33.2k
4
votes
3
answers
1k
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an esoteric matchbox
Seeing a vast repository of matchstick puzzles, Professor Moriarty determined to create one of his own. Behold, his greatest crime yet, the best and worst matches puzzle to ever grace this earth with ...
- 550
9
votes
1
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Fitting snakes in a cage
11 snakes are in a 6x11 rectangular cage (grid) in a zoo.
Each snake is a different length, from 1 to 11.
No snakes may overlap. No spaces are empty.
Each of the 6 rows may contain at most 2 snake ...
- 24.5k
3
votes
2
answers
698
views
The Diamond of Columbus
There are up to flipping / rotation 12 distinct pentominoes.
Can you fit them without overlap in the white area?
- 19.1k
10
votes
4
answers
2k
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A Prime Number equation using all nine digits once
Create an equation with the following conditions
All numbers must be one or two digit prime numbers
You can only use + and - and =
No other math operators
You must use all the nine (single) digits (...
- 5,407
10
votes
2
answers
430
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Shiny cryptarithm
Here's a little puzzle I made today:
$$\sqrt{\text{ILLUMINATE}^{\mathstrut}} = \text{LIGHT}$$
Most usual rules of alphametic puzzles apply here: the same letter always represents the same digit, and ...
- 1,151
18
votes
3
answers
2k
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Playing Mastermind against an angel and the devil
This puzzle is based on a card game. There are 7 suspects and 3 of them committed a crime. The game contains 35 cards that contain the 35 possible choices of 3 out of the 7 suspects. One card is drawn ...
- 1,691
8
votes
0
answers
487
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27 spaces, 27 curious places
Grid 1:
Grid 2:
Grid 3:
Find the meaning behind these images.
Hint 1:
- 821
3
votes
1
answer
243
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Justifying a redouble
This puzzle is derived from a real game of bridge I played on Bridge Base Online.
I was sitting North on board 9 (N dealer, E-W vulnerable) and the bidding turned out like this:
West
North
East
South
...
- 6,996
0
votes
1
answer
152
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Techno-Culinary Brain Teaser: Unravel the Code in the Kitchen
The answer is one word.
The rebus:
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1
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0
answers
181
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5
votes
1
answer
369
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Find the ciphering method 2
Link to the entire series.
The message:
3, 53, 48751, 9247757, 294914580539
The answer is a 13 letter word: UNDERSTANDING
Hint 1:
- 821
2
votes
1
answer
265
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Find the ciphering method using deciphered message
Link to the entire series.
Ciphered message:
...
- 821
0
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0
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73
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Find the largest number with unique digits, that is divisible by each of its digits [duplicate]
Find the largest number with unique digits, that is divisible by each of its digits.
For example 132 has unique digits and is divisible by 1, 2 and 3. But it is not the largest such number. Can you ...
- 161
32
votes
13
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8k
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2 vs. 1.005^200
Without using a calculator or a computer can you determine which of these two numbers is bigger: $2$ or $1.005^{200}$ ?
I saw this puzzle in a YouTube video, which I will post later.
- 33.2k
-2
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1
answer
116
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Fill a 4x4 grid with minimal sum of positive integers in a way that adjacent cells contain numbers of different parity
Find a 4x4 grid containing 16 unique positive integers with minimum sum, such that adjacent numbers have different parity.
- 821
6
votes
1
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303
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The Nine Gardens Of Eden
This puzzle is part of the Monthly Topic Challenge #11: Now in 3D.
There are nine distinct known three-cell Garden of Eden patterns in the Life Without Death cellular automata, including the two well-...
- 2,699
1
vote
1
answer
264
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A take on custom ciphers
There is something hidden in the text below. Can you find out what it is? Note: no computers or tedious work required.
...
- 769
12
votes
3
answers
4k
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I Hate Traffic And So Do You
I need to travel through the city from my house to school, but the traffic is horrible right now.
I can only move along the city's grid with the following conditions:
• blocks with traffic (marked in ...
- 574
2
votes
1
answer
248
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The minimalist game master [closed]
A game master tells his party of players that he has converted to the school of minimalism, and is going to do away with all of his dice in the campaigns they play from now on. In the place of dice, a ...
- 2,349
0
votes
0
answers
153
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Puzzle "railway game set"
Alisa completes a railway game set which allows us to make various closed railway routes with crossroads. It is need to put the “rails” parts in the kit, as well as four types of “crossroads”: corner (...
- 1,699
-3
votes
1
answer
190
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Giraffe Necked Island
Where is this island, and why is the title of this question "Giraffe Necked Island?"
- 331
4
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1
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309
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A different Crack the Code puzzle
This is a different Crack the Code and get the word puzzle. Here, instead of letters, actual words are hidden.
The final word is a 7 letter famous person. That word consists of several words. I only ...
- 5,407
3
votes
1
answer
357
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Micropoker: small hands on deck
Raise your hand if you are ready for micropoker,
which minimalistically resembles
5-card poker.
The deck has just 8 cards with 2 suits of 4 cards each.
A hand is dealt as 3 cards that are final, with ...
- 21.8k
20
votes
7
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1k
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Save now! All the digits at half the price
... or double the price depending on where you're coming from
Consider the set $PD10$ of pan-digital ten-digit numbers, i.e. positive whole numbers whose decimal representation has each of the digits ...
- 19.1k
9
votes
1
answer
1k
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Important Alien Message
A strange alien transcript, alongside what is believed to be a partial key, was recovered the other day. Scientists aren't sure what the message might contain, but theories point to some sort of ...
- 539
13
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1
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Find the lower 8-digits number such that
This one come from newspapers in France, where this week is the "mathematics week", and some problems are proposed to kids.
This single one is easy and funny:
Find the lowest 8-digit number, ...
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10
votes
1
answer
299
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Equilibrium of differences
There is a subtraction equation written on the board, with three digits minus three digits, and the first digits both fixed. Alice and Bob need to fill in the remaining 4 digits (A~D below) using 4 ...
- 928
10
votes
1
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897
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Numbers whose product of digits is a multiple of sum of digits
Find three consecutive numbers, greater than 10 and none with a digit 0 in it, each of which is such that the product of its digits is a multiple of the sum of its digits.
What about four or more such ...
- 16.9k
3
votes
1
answer
350
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How to find the value that makes this addition equation work without using a computer?
The following image represents the addition of 2 five-digit numbers, where 10 different letters represent 10 different numbers (0~9). What does PUZZLE equal? (There are two possibilities and a ...
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12
votes
1
answer
695
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Friends and Enemies
Here is a short puzzle I made:
There are 10 people arranged in a row, and each of them has a friend and an enemy also present in the row. Your goal is to identify the friend and enemy of each person.
...
15
votes
1
answer
533
views
What does the fox say?
I found a piece of paper on the hallway floor of my friends apartment complex, and on it is an oddly written question and an unreadable response. Can you figure this out?
Question:
WHAT DOES THE FOX ...
- 2,438
15
votes
1
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1k
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Trust me: you do not want to go down this road with me
Every cell has a digit from 0 to 9 or one of the four operation symbols +, −, ×, and /, signifying addition, subtraction, multiplication, and division respectively.
No digit appears more than once in ...
- 12.6k
3
votes
1
answer
252
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Two many restrictions
Using only the number 2 several times, form the numbers 2, 22 and 222.
The following operations are available:
addition
subtraction
multiplication
division
exponentiation
Each of these operations ...
- 2,694
5
votes
1
answer
325
views
What is a Nature Word™?
This puzzle is in the spirit of the What is a Word/Phrase™ series started by JLee with a special brand of Phrase™ and Word™ puzzles.
If a word conforms to a special rule, I call it a Nature Word™.
...
- 803
-5
votes
1
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What season was it?
A puzzle maker wrote this in his notebook as a holiday puzzle:
Th bbie sartd unning.
What season was it?
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votes
3
answers
599
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125034 v1.0.0 / WR 1713-11-07
I am developing an app that generates puzzle games every day (https://125034.pages.dev/).
Their basic form may be viewed as Wordle in math, Sudoku in 6 grids, or Einstein's Riddle in 1 row.
If today ...
- 13
28
votes
2
answers
2k
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A logician's Bingo
Mark some cells on the following Bingo board, so that all statements in marked cells are true AND all statements in unmarked cells are false.
A Bingo here is a set of five marked cells in a row, ...
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5
votes
3
answers
420
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Laziest Checkmate
Consider a game of chess where White delivers checkmate in their $X^{th}$ move. For all the pieces that remain on the board at the end of the game, consider their Manhattan Distances from their ...
- 2,694
4
votes
1
answer
181
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Packing the Primes
Here is a 5x4 rectangular wordsearch (area 20) containing the primes between 1 and 100,
{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}
(numbers in any ...
- 24.5k
10
votes
3
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2k
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The Universe's Secret
To find the universe's secret, first solve the Sudoku variant with #s 1-7 only.
No number may be repeated on any diagonal. No numbers go in the squares with red or green dots.
Then use the solution ...
- 17.5k
5
votes
6
answers
416
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How many digits does $7^{100}$ have?
I'd like to estimate $7^{100}$ without using these new-fangled computers everyone is talking about, but I think I need your help.
Please estimate $7^{100}$ without the use of a computer. My friend ...
- 153