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1500 questions
52
votes
4 answers
The lion and the zebras
The lion plays a deadly game against a group of 100 zebras that takes place in the steppe (= an infinite plane).
The lion starts in the origin with coordinates $(0,0)$, while the 100 zebras may arbitrarily pick their 100 starting positions.
The the…
Gamow
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52
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5 answers
A five card trick - How does it work?
At a party last night, my friends Alice and Bob did a magic trick. Any ideas how it worked?
Alice shuffled a pack of cards, and asked me to take five. I looked at them. She put the rest of the pack down on the table. Alice asked for my cards. She…
Colonel Panic
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52
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7 answers
Does the drunk man fall off the cliff? (a random walk problem)
A drunk man stands with a cliff one step to his left.
He takes steps randomly left and right.
Each step has probability $p$ of going left and probability $q=1-p$ of going right.
Each step is the same size.
If allowed to randomly step indefinitely,…
DanielSank
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52
votes
3 answers
Is the magic liquid in the bottle safe to drink?
You buy a bottle with a letter from the merchant, the merchant tells you that when you drink the liquid in the bottle it grants you eternal life, he supposedly deciphered this from the letter.
After you get home you decide to study the letter if…
Vajura
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52
votes
9 answers
How Big is Your Vocabulary?
Can you guess what I am?
Sometimes I hang out with the Pope,
Other times I spend my time in the country.
I do not have just one correct spelling, but two.
A botanist would describe me as a shape of a plant.
I can be functional, symbolic, or even…
Crozier
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52
votes
4 answers
Desert Irrigation Project
An entry in Fortnightly Topic Challenge #32: Grid Deduction Hybrids
My dear friend researches and designs canal irrigation systems in a remote desert. He's been missing for two weeks. Members of his research team have reported erratic changes in…
paramesis
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52
votes
3 answers
A very unique chess puzzle
Find a legal move for white that does NOT mate in one.
Source: by Karl Fabel & was reprinted in Martin Gardner's New Mathematical Diversions from Scientific American (pub. Simon & Schuster), ch.19, p.223
Quintec
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52
votes
2 answers
A crossword so simple, it practically solves itself
An entry in the 19th fortnightly challenge...
A Grid
Some Clues
There are three examples of this in the finished grid
Two answers that touch a corner, in relation to 25A (D)
Contained in the rotational symmetry of the grid
The clue above…
Alconja
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52
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3 answers
Find the treasure before Dargloc does
Some time ago I met an old man who handed me a scrap of paper and told me:
Dargloc - the treasure hunter is searching. You must be quicker. The key to success is to obey the rule:
"If Dargloc rests now? You have to hurry." But do not dare to repeat…
oleslaw
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52
votes
2 answers
Ron couldn't quite put his finger on... something?
Ron got up out of his bed, feeling slightly odd. Despite only being conscious for under ten seconds, he felt like something recently slipped his mind, something he couldn't quite put his finger on.
He shuffled to the toilet, thinking if it could…
Mike.C.Ford
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52
votes
4 answers
What is the best method of scrambling a rubik's cube?
If I wanted to solve a physical Rubik's cube multiple times, for practice, what is the best, most random way, to scramble the solved cube?
The best way I can think is to hold it behind my back and turn randomly until, when I look at it, it looks…
David Wilkins
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52
votes
4 answers
Batman and the piano
Batman: Alfred. Are you there?
Alfred: Yes, Master Bruce. How may I help you?
Batman: I'm still in pursuit of The Riddler, but I've run into a problem. I've been trapped in a room with a piano, and two paintings on the wall. One of these…
Khale_Kitha
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52
votes
11 answers
Turning a goat?
This is a goat made up of 5 sticks. You have to move (change position) any one stick of them such that its head turns to the right side (above the right leg).
Notice currently its head is on the left side and above the left leg.
Part 2- Turning a…
prog_SAHIL
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52
votes
1 answer
Help! I can't rock out, with my clock out!
I need your help! Look at this:
One, two, one o'clock, three o'clock rock
Eight, six, three o'clock, two o'clock rock
Nine, seven, one o'clock, seven o'clock rock
We're gonna rock around the clock tonight
There's no way I can possibly rock to my…
Alconja
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52
votes
2 answers
Four-words (----||||)
Four-words:
My first is indivisible, but not really.
My second is a cloak worn by men, but in ancient Rome.
My third is a cruel wicked person, but not a human.
My fourth is about 20 quires, but in reverse.
I was not allowed a very short title for…
Prem
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