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1500 questions
47
votes
4 answers
Who am I??? Wait, isn't this a sudoku?
Jmw jrr qtlf tv ee M6SXr rro tr kz r tyr.
Can you find out who I am?
Hint 1:
Some parts of the puzzle have been used multiple times to guide you in the right direction.
Hint 2:
The numbers discovered by @Levieux are practically final and it…
Maria Ivanova
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47
votes
12 answers
The SErial Killer (Part 1)
This is part of a series which I'll be continuing if this goes down well enough. If you have any feedback on the puzzle (too hard, too easy, not clear enough, etc) I'd appreciate it so that future puzzles can be better :-)
You wake up and log on to…
Joe
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47
votes
6 answers
A-maze-ing Dice
This is an entry to the 12th fortnightly challenge
"So you have escaped my labyrinth of words, and now you think you are free, do you? Well, I have news for you: Think again! Ha Ha Ha Ha"
Having just left the maze of words, your spirits sink to an…
BmyGuest
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47
votes
2 answers
Why did John buy so many batteries?
World-famous engineer John Johnson decided to take a break from his latest invention, and asked his wife if she had any chores he could do to clear his mind. She handed him a grocery list and told him to go to the store. The list contained perfectly…
Devsman
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47
votes
6 answers
I am both lock and key - who am I?
Enter! Small or large, as the case may be
I'll assist you - it's easy! - I'm both lock and key
Who am I?
user17947
47
votes
4 answers
Which switch goes to which bulb?
You are in a room with three switches, labeled $A$, $B$, and $C$. Initially, each switch is in an off state. In an adjoining room, there are three incandescent light bulbs. Your task is to correctly label which switch goes to which bulb.
The…
Xynariz
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47
votes
4 answers
Famous eater. Who am I?
Although I've never been interviewed,
I'm famous all over the world.
People love to watch me eat,
But some disapprove of my habits.
I don't mind working for my food,
And I like to eat on the run.
Picky, I eat only 3 foods,
Not counting my…
JLee
- 18,202
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47
votes
5 answers
How do I force-quit the program?
My friend has been playing with a program he found. He enters a 5-digit number into the command line and receives another 5-digit number in return. However, after 20 or so entries, he's about done and ready to quit. Unfortunately, there doesn't…
Bailey M
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47
votes
10 answers
1 2 3 4 5 6 7 8 9 = 100
The sequence of numbers $1\ 2\ 3\ 4\ 5\ 6\ 7\ 8\ 9$ has the property that you can insert mathematical operators in between the numbers from $1$ to $9$ and make the expression evaluate to 100. For example:
$$1 + 2 + 3 + 4 + 5 + 6 + 7 + 8 \times 9 =…
anon
47
votes
1 answer
Which country flags can you make in Tetris?
Your friend is playing Tetris. In her version of the game, the pieces use the standard colors and can drop in any possible order without restrictions. In the order shown below, the colors are light blue, dark blue, orange, yellow, green, purple, and…
noedne
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47
votes
2 answers
The mystery of NOC +10
NOC +10
On March 6th, 2015, a YouTube channel named "Noc +10" was created. Since that day, this channel is uploading some really darkly mysterious videos. I will start saying something about the name of this channel, which is pretty odd, indeed:…
Marco Bonelli
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47
votes
3 answers
Animal Cross(word)ing
An entry in Fortnightly Topic Challenge #43: Variety Crossword Grids
Each of the 40 clues listed below (a mix of pop culture and science/nature) yields the name of an animal. Your task is to solve the clues and enter their solutions into the…
Stiv
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47
votes
4 answers
The coolest checkerboard magic trick
In the small town of Terni (Italy), there's a couple of young friends named Marco and Leonardo, who like to perform magic tricks to a restricted audience of common friends and relatives. They like to call themselves "The prodigious Duo". Every…
Marco Bonelli
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47
votes
5 answers
TRUMP to BIDEN : This transition won't be easy
Can you change the word TRUMP to the name BIDEN in 10 steps or less by
changing one letter at a time?
Each change must result in a valid word from MW dictionary.
No proper nouns, abbreviations or acronyms. No rearrangement or anagrams either.
Have…
DrD
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46
votes
4 answers
x⌊x⌊x⌊x⌋⌋⌋ = 2020
Solve for $x$:
$$
x \left\lfloor x \left\lfloor x \left\lfloor x \right\rfloor \right\rfloor \right\rfloor = 2020.
$$
The floor function $\left\lfloor t \right\rfloor$ has the usual “greatest integer $\leq t$” definition.
Attribution pending From…
Roman Odaisky
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