All Questions

This crossword is themed, and in fact, the theme is revealed in the unclued answer. Note that some of the clues won't make a lot of sense without knowledge of this theme, as I couldn't find much in ...

This 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 Valid Word™. Use the ...

If you are given a transparent weirdly shaped bottle filled with water and a marker, can you tell if the bottle is exactly half filled or not?

Place 19 different positive integers on the vertices of this graph so that the 13 products of three numbers in a straight line are all equal. Do so in such a way that the product is as small as ...

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...

A professor decides the following grading scheme in his class. After the final exam is graded, he keeps all the papers upside down on his table in a random order so that no student can recognise his ...

Two cities A and B are 100 miles apart. A person has to travel from one city to the other in his old old car, which can travel only 50 miles with its tank full. Unfortunately, there are no gas ...

There are ten wires that run underground across a river. Thus on each of the banks, there are ten ends of the wires. Unfortunately, given an end of a wire on this bank, one doesn't know which end on ...

I've tried to solve this question(Exercise 31) in many ways but I couldn't figure out the logic behind this.

Here is a short puzzle story that I created. People on other forums seem to not understand it for some reason, but everyone I spoke to in real life understood it. But no one I knew so far got it right ...

It's White to move and checkmate Black in 36 moves. I have slightly changed the original stipulation. Feel free to explain the title if you want to! Source(Couldn't copy and paste!): P.S.-How has ...

Anchor's away! Ahoy, puzzlers, I am Cpt. Wesley Wordsquare. I'm about to set sail for the mainland to see a show at my brother Winslow’s Wordsquare Theatre, however I can't seem to decipher this ...

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...

The Leadman was instructed that on each floor level of the building under construction, there shall be two workers assigned to do some job. There are seven workers on the ground floor and five workers ...

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Change my first, I'm entertaining Change my first, I can kill Change my middle, I'll be over Change my middle, I'm some bloke Change my last, I'm made of skin Change my last, ...

I saw this puzzle on this address. $3+5+7=152181$ $4+5+6=202461$ $3+4+7=122172$ $9+4+5=364518$ $8+6+8=?$ I know that first $4$ digits are $4864$. How could I find last $2$ ...

In the spirit of the What is a Word™/Phrase™ series started by JLee, a special brand of Phrase™ and Word™ puzzles. If a word conforms to a special rule, I call it a Motley Word™. Use the following ...

I have 8 balls and one of them is lighter than others. How could I find that ball by 2 tries? Also I have a balance scales.

So, we all know the famous 12 balls 1 scale riddle. It has been here repeated many times, however, the provided solutions always start with splitting the twelve balls into three groups of four. This ...

Can you make $2471$ using first seven powers of two: $1,2,4,8,16,32,64$, each exactly once? Only the basic operations are allowed: $+,-,\times,\div$, and parentheses $(\space)$. ...

You've been approached to assist in the furtherance of SCIENCE as a research subject at the Institute of Mad Science (local branch)! The experiment you'll be involved with is called the Sleeping ...

This is a Heyacrazy puzzle, designed at request of testsolvers of previous puzzles who wanted to see how longer diagonals would work. Rules of Heyacrazy: Shade some cells of the grid. Shaded ...

I have been trying puzzle solving recently and came across this problem. Any hints on how to do this? So far, I have found that N, R and F must be odd (as they are the last digit in a 5 digit prime ...

It's been a while since I've posted, and in the spirit of my recent works, I've got a simple riddle to get back into the swing of things. As always, I hope you enjoy it, and best of luck! After the ...

Find the next two numbers in this series $ 5, 9, 4, 5, 7, 1,...$

can you guess? i know its a simple puzzle but lest just have fun

This 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 CirKle Word™. Use the ...

I planning a surprise trip for my husband's 40th. He is a math geek. I am not. My plan is to tell him in a series of riddles/puzzles that he needs to figure out. We are going to LA to see his ...

This puzzle is a combination between a Slitherlink and a Fillomino. You should put a number in each square and draw a single closed loop over the grid such that the following properties are satisfied:...

Each answer to a clue will consist of the titles of two works or series put together, where the last word of the first title matches the first word of the second title. Note that the word match does ...

It's White to move and draw the game. What must White do? You must provide proof for your claim of what's to be done by any reasonable means. This puzzle was created by Nikita M. Plaksin, and ...

Inspired by A double-agent with a conundrum. Everything is hypothetical and while the choice of countries are important, they serve no political purpose. Tension between the US and China is rising. ...

Following the last question " What is the corner house number?" here is possibly a more challenging version. Fill in the missing house numbers on the map shown below. The area is occupied by math and ...

There is a very well-known family of right triangles in Mathematics called "The Imperial triangles". Let me explain you how they are defined: We say $T_n$ is the $n$-th Imperial triangle if these two ...

Well, my friend told me that he's just visited a safari. Being toured around, he was very surprised how the guide could spot those animals so quickly. He took some pictures of the animals, ...

Some time ago, I discovered that planet earth's sidereal rotation period equals 23 hours, 56 minutes, and 4.1 seconds (see for example this Wikipedia article). The sidereal rotation is the rotation of ...

It was a bright and sunny day during April- May(can say, peak of summer) in a country in the northern hemisphere, near to the equator. I was wandering(on foot) through this country's vast and open ...

In the year 2407476658354979366708415043923125501315337890943021769230219230892355006879909214795402102204224, as cosmopolitanism is in the air and companies are more than ever bound to ...

This is a Heyacrazy puzzle, originally constructed for a test for Logic Masters India. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded ...

Three colleagues at the bank are boasting to each other… Colleague 1: “Ask anybody – I’m clearly the best.” Colleague 2: “And how do you figure that?!” Colleague 1: “Well, just ...

Sometimes it's difficult for outsiders to understand what brings a couple together. What brings each of these couples together? ...

A quick teaser, enjoy! Across 3 Dance bores serious (5) 6 Light angry look (5) 11 Finally asked it to agree (5) 12 Rails - cunning homes of thieves (5) 15 Trap saner design (5) 16 Kingdom with real ...

This is a Heyacrazy puzzle. Rules of Heyacrazy: Shade some cells of the grid. Shaded cells cannot be orthogonally adjacent; unshaded cells must be orthogonally connected. When the puzzle is ...

In my home is a common household object. I securely attached a marking pen to some point on the household object, and I placed a sheet of graph paper next to the pen, so the paper would not move. I ...

Contrary to the lazy puzzler, the creator of this masyu is too ambitious that he adds not only one but two extra stones, so the puzzle is unsolvable. Finish his job for him by removing those ...

These three belong to three different clubs. First one, very popular, is singles only club. It is closed for new membership. Second one, very useful, is for singles and couples. It is open ...

This is actually coming from a business place, but it's all about being able to do math tricks, and that's why I'm posting here. I want to implement the following function: ...

I went to a play recently. Immediately after the intermission, some cast members sang this short (and terribly written) song: This treatise we sing on this section of stage is not so long as to ...

This 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 an Independent Word™. Use ...