Puzzleprime Difficulty Advanced
π₯ Insight β’ Advanced
The Pizza and the Clock
How can you split a pizza into 11 equal pieces, using just one clock?
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π₯ Riddle β’ Advanced
Throw It and Bring It Back
If you throw me from the window,
I will leave a grieving wife.
Bring me back but in the door,
And youβll see someone giving life.
What am I?
I will leave a grieving wife.
Bring me back but in the door,
And youβll see someone giving life.
What am I?
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π₯ Deduction β’ Advanced
The Ping Pong Puzzle
Three friends β A, B, and C, are playing ping pong. They play the usual way β two play at a time, the winner stays on the table, the loser lets the third one play. If you know that A played 10 matches in total, B played 15 matches in total, and C played 17 matches in total, who lost the second game?
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π₯ Mathematics β’ Advanced
Consistent Polyhedron
Can you construct a convex polyhedron, such that no two of its faces have the same number of edges?
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π₯ Chess β’ Advanced
Monochromatic
If you know that the following game has been monochromatic, i.e. no piece has moved from black to white square or vice-versa, which one is the correct position of the bishop β e3 or e4?
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π₯ Riddle β’ Advanced
Never in a Thousand Years
What occurs once in every minute, twice in every moment, but never in a thousand years?
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π₯ Mathematics β’ Advanced
Mysterious Polynomial
You are given a polynomial P(x) of unknown degree with coefficients which are non-negative integers. You donβt know any of the coefficients, but you are allowed to evaluate the polynomial at any point you choose. What is the smallest number of evaluations you need to use, so that can find the degree and the coefficients of P(x)?
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π₯ Insight β’ Advanced
10 Prisoners, 10 Keys, 2 Weeks
One day, the warden of a prison is, like most wardens in puzzles, feeling a little capricious and decides that he wants to get rid of his prisoners, one way or another. He gathers all the prisoners in the yard and explains to them β βTonight, I will go to each of you, hand you a key, and tell you who has your key. Each day after that, while the others are out of the cells and no one is watching, I will allow each of you to place your key in someone elseβs cell β and each night, you may collect the keys in your own cell. If at any point, you are certain that everyone has the key to their own cell, you may summon me, at which point each of you will open your own cell and walk free. If anyone has the wrong key, everyone will be executed then and there. You may discuss your strategy before tonight, but afterward, no communication will be allowed regarding my game. β Oh, and by the way, if you are still here two weeks from today, I will execute everyone β itβll be a big birthday for me and I want to retire!β
That night, just as promised, the warden went to each cell and gave each prisoner a key. As he handed each prisoner the key, he whispered to them the name of the person possessing the key to their cell. The keys were entirely indistinguishable from one another, but that was okay, because the prisoners had not counted on being able to tell anything about them. Indeed, the prisoners all seemed confident.
What was their strategy? How could they beat the wardenβs game?
That night, just as promised, the warden went to each cell and gave each prisoner a key. As he handed each prisoner the key, he whispered to them the name of the person possessing the key to their cell. The keys were entirely indistinguishable from one another, but that was okay, because the prisoners had not counted on being able to tell anything about them. Indeed, the prisoners all seemed confident.
What was their strategy? How could they beat the wardenβs game?
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π₯ Mathematics β’ Advanced
NASA and the Meteor
NASA locates a meteor in outer space and concludes that it has either a cubical or spherical shape. In order to determine the exact shape, NASA lands a spacecraft on the meteor and lets a rover travel from the spacecraft to the opposite point on the planet. By measuring the relative position of the rover with respect to the spacecraft throughout its travel on the planet (in 3D coordinates), can NASA always determine the shape, no matter the route taken by the rover?
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π₯ Insight β’ Advanced
The Poisoned Glass
You are given 4 identical glasses, completely filled with transparent, odorless liquids. Three of the liquids are pure water, and the fourth is poison, which is slightly heavier. If the water glasses weigh 250 grams each, and the poisoned glass weighs 260 grams, how can you figure out which one is which, using a measuring scale just once?
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