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For puzzles that presented themselves, with real parameters and consequences, during otherwise non-puzzling activities.

7
votes
2answers
866 views

Don't put yourself out, dear

I asked my mother the other day, "What do you want for dinner? I'll get you anything your little heart desires." My mother, true to form, radiated the stereotypical motherly vibe: "Don't worry about ...
6
votes
6answers
292 views

Flipping a coin across the internet

Suppose you wish to "flip a coin across the internet". ie. You want to show other people that you've flipped just ONE coin, and show them the result. I'm currently trying to think of the simplest ...
15
votes
1answer
3k views

My teacher gave me a puzzle one day

I told my teacher that I liked riddles and puzzles. As a matter of fact, I introduced him to the Puzzling Stack Exchange! Then, he got a sheet of paper, asked for a pen, and when he found one (I didn'...
6
votes
2answers
276 views

Identical-Looking Keys on a Ring

The number of keys on your key ring has been growing steadily over time, and now you already have 15 keys to keep track of! Unfortunately, you are unable to distinguish one key from another (apart ...
7
votes
5answers
249 views

Selecting the starting player [closed]

The board game is about to begin. And suddenly we realize that we need to decide the starting player. The dice procedure is tiresome. And we can't find our dice right now. Or any other artifact that ...
9
votes
1answer
296 views

We're gonna need a bigger bowl!

It's time for lunch, and I want to eat my favorite Regresso™ Chicken Noodle Soup. Ideally, I would pour all the soup from the can to my bowl, microwave the bowl, then eat the soup. Unfortunately, ...
2
votes
2answers
179 views

What are the chances on watching the clock? [closed]

This is a relatively straightforward little puzzle, but the answers are somewhat unintuitive or can prompt a new perspective. It might be an interesting little puzzle for a probability teaching ...
4
votes
0answers
240 views

Is there a hidden message this old Polybius listing?

I recently watched this video about the mythical arcade game Polybius. It's a well-crafted investigation that thoroughly debunks the myth, but there's a segment in which the investigator suspects a ...
29
votes
9answers
9k views

Should I Take the Bus or Refill My Bottle First?

This is a real-life puzzle encountered by one of my friends. I want to arrive early to my class today. Exactly every $7$ minutes, there is a bus that arrives at the station near my dorm and will ...
59
votes
7answers
23k views

My friend sent me a photo of his keyboard, but there's something I can't figure out about it

Two months ago, my friend bought a new Chromebook. He told me yesterday that while he is happy with the computer overall, he's not that impressed by the quality of the keyboard. My friend is an ...
11
votes
1answer
753 views

Who can solve this cipher?

The following cipher is moderately difficult but not impossible. It is (IMO) probably easily solvable for an experienced professional code breaker. ...
1
vote
4answers
419 views

The helicopter position?

Helicopter fly from New Jersey to the north for 500 km and then to the east 500 km, then to the south 500 km and then to the west 500 km where is she now? Can it arrive at a position where ...
34
votes
6answers
5k views

Changing baby's shirt

Baby needs a change of shirt, but baby is also sucking on a bottle (see this stock photo for a visual). If the bottle leaves baby's mouth, baby will start crying. Also, baby loves holding the ...
0
votes
4answers
433 views

What is the name of the novel?

Yesterday, after I picked up my son from fencing practice, we stopped at Krispy Kreme to get doughnuts, as per our tradition. The total was $3.19. I paid with a five dollar bill and when I got my ...
2
votes
1answer
260 views

Scheduling Meetings

I came across this problem in real life and thought it could be made into an interesting puzzle. I will enjoy seeing how my eventual solution could be improved! Here's the situation. There ...
9
votes
1answer
620 views

What does this symbol mean

This is a real life question. I have a hat that has this symbol on it I can't figure out what it means. I have asked everyone I know. But I didn't get good answers. So What does it mean? Even if ...
23
votes
15answers
10k views

Separate the milk!

You have a jug of milk and a jug of water. You must empty both jugs into a nine gallon barrel. You must be able to: Differentiate between the milk and the water Separate the milk from the water You ...
-2
votes
9answers
2k views

Ice Cube Lifting Puzzle [closed]

Here's an interesting scientific problem. Drop a small ice cube into a partially filled glass of water. Next, get a foot-long piece of thread or string. The puzzle is to remove the ice cube from ...
2
votes
2answers
251 views

Longest autological loop?

A word is said to be autological if it describes itself. This can be a property of both nouns and adjectives; for example, "noun" is a noun and "pentasyllabic" is pentasyllabic. We can also construct ...
9
votes
2answers
816 views

Find Four Pins of 50 in this Image! — A Hidden Object Puzzle

Tonight, my friends and I went to the mall. We planned to buy some shirts and pants, but suddenly... we found this! These are number/size pins. They are typically used in hanger to denote the size of ...
2
votes
2answers
378 views

How to Charge Our Devices in this Machine?

Warning: It is actually a simple "puzzle" which is silly but debatably unique as it really happens to me in real life. I'm amazed with nowadays technology. When I go to one of the shopping mall in ...
15
votes
5answers
2k views

Optimal Money-Saving on the NYC Metro

You are on vacation in New York City. You didn't bring your car, and it's currently around $-50^\circ C$, so it's probably a good idea to take the NYC metro subway to move around. You need a metro ...
0
votes
2answers
146 views

Pray they can hold it in for two hours? [closed]

I use to to help with the nursery at a very small church. The Nursery was downstairs next to the the two small restrooms for males/females. Whenever I had to go out to a restroom to get towels or ...
-6
votes
3answers
428 views

What do these two places have in common?

In the United States of America, the New York City Borough of Queens lies at the west end of Long Island. More than 5000km across the Atlantic ocean lies the Metropolitan Borough of Bolton, a borough ...
5
votes
2answers
313 views

Improve my 3D puzzle

3D View of one solutions http://autode.sk/2Dg4FWx I designed a 4x4x4 soma cube in AutoCad and then built it with wood cubes. There are twelve pentacubes and one tetracubes. Each piece is unique and ...
15
votes
1answer
669 views

Code Cracking 1984

This is a code from an old home computer magazine. Still it is unknown the cipher used for it, although they gave the solution: ...
-4
votes
2answers
361 views

Length of mystery object

What everyday object is ${n}^{-1/4}$ metres long, where $n$ is an integer? Hint: n= Note there may be some cultural dependence here.
-3
votes
2answers
213 views

A toy needs 3 batteries, but I only have 2 batteries [closed]

I have a boy, he has a toy which need 3 batteries, but I only have 2 batteries. With an easy hack I can switch on the toy to work properly. What did I do?
54
votes
22answers
12k views

Can you open the bathroom door? [closed]

This happened to me in a rental apartment and I had to be creative to solve it. The geniuses who designed the bathroom managed to fit a drawer about a centimeter behind the door, and eventually what ...
23
votes
1answer
1k views

What is the solution to Lewis Carroll's “Froggy's Problem”, and what is the “trap”?

Froggy's Problem was presented in Lewis Carroll's Symbolic Logic, with a note that it "contains a marvellous trap". Because Carroll never released Part 2 of Symbolic Logic, its solution is unknown. ...
3
votes
1answer
288 views

Floored and foiled

Scene 1 – A hallway There I was, in a corporate hallway 110 shaftments long (approximately 18 m or 60 ft) and unspooling a 100 -shaftment length of cable from a reel. All too ...
8
votes
1answer
585 views

The tomb with the answer to life

Diophantus was a famous ancient Greek mathematician. This was carved on his tomb: Herein lies the remains of Diophantus. God vouchsafed that he should be a boy for the sixth part of his life; when ...
5
votes
0answers
437 views

Need help with a cipher

I am trying to figure out a cipher I think I found in a book from 1982 and it's a 35 year old mystery we are trying to solve (I will reveal the book if this turns out to be something so everyone can ...
20
votes
2answers
2k views

Who is Panama Oxridge?

Panama Oxridge is the author of a children's book series about a boy called Justin Thyme. However, the name Panama Oxridge is actually a pseudonym for an unknown author. From the series website: ...
-4
votes
1answer
251 views

Which screws go first?

Humans are not always accurate at measurements. I recently got a table top that came with an attachment. Table top and attachment are nearly of same size and rectangular with four screw holes near ...
6
votes
1answer
396 views

Picture a graph without words

You may have played/sung/heard a song without words in concert, in choir, and in a Sushi restaurant. Who hasn’t?! Well here is a picture without words, only axes: And here it is without JPG-...
22
votes
14answers
1k views

The master programmer and the mystical reversal

The master programmer sat at his desk, gazing into the distance, his eyes seeing, and yet unseeing. The lunch had been heavy. His reverie was interrupted by the appearance of his close colleague, ...
9
votes
3answers
467 views

Ridge Trail moisture mystery

(click to visit this picture via Google Street View) The weather was less pleasant than pictured above but the afternoon began nicely enough that I wasn’t about to waste an hour already ...
-1
votes
10answers
1k views

Leave a room without entering it first

This is a quick little puzzle that requires a bit of lateral thinking. Today, my boss physically walked out of her office (her private room in the larger office), but she never physically entered her ...
15
votes
10answers
1k views

Two many rainbows?

Wish I’d had a camera at the time but a cartoon will have to suffice, representing two actual incomplete rainbows that stop in midair where they meet, lit only by a setting sun. This seemed so ...
11
votes
1answer
320 views

Binary coded message on a house in Catalonia

I found this inscription on a wall of a house in town of Martorell, Catalonia, Spain. It looks rather modern and I think its creator ciphered some word / message / joke in it. I tried to lookup ASCII ...
5
votes
8answers
698 views

A strange sight in London

While travelling in London, I noticed something strange. I saw some numbers which appeared to be counting up but which then switched to counting down. Later on, I saw the same thing, but the numbers ...
20
votes
1answer
2k views

Ricky McCormick's Notes

On June 30 1999, Ricky McCormick was found dead in an isolated area, 15 miles away from his home. He didn't own a car, and the area was not subjected to public transport so it is a mystery how he got ...
2
votes
2answers
324 views

Steganography TriBond™

These three have a technological attribute — me — in common:    •   What does each of these represent? •   How ...
9
votes
4answers
426 views

Mystery on the trail to Dutch Flat

On a recent amble, I happened upon a sign $\small \raise2mu ( {\normalsize\sf\color{#d90} A} \raise2mu )$ that seemed to indicate a mistake — or— a mystery. ...
26
votes
4answers
2k views

This image contains a “Great Discovery”

The Puzzle: Source material taken from here As discussed on Numberphile, here is John Herschel's doodle, sent to his friend Charles Babbage. John H. John Herschel was an English polymath, ...
27
votes
2answers
4k views

Does this metal puzzle have a solution (Baguenaudier)

When I was young I got this puzzle as a gift to me. The aim is to get the long piece out. I haven't yet found a solution, and I'm not sure if there is one Does this have a solution and if so ...
12
votes
21answers
780 views

The Empty Elevator [closed]

This is a lateral thinking puzzle based on my real life: Earlier this evening I got into an empty elevator, pressed a button for a floor, and walked out before the door closed. I wasn't being ...
9
votes
2answers
342 views

Third timer's a charm

Three motorized 24-hour light timers are arranged between a power outlet and a light bulb, with timer A parallel to a daisy chain of timers B and  C. For these timers, devise schedules that ...
3
votes
2answers
1k views

How to solve an Enigma Puzzle without indication?

A friend of mine just wrote one thing on a board : TEJDAO QZ OCUQJ UVANBVCR The only indication was "Enigma Puzzle". If it is really an Enigma like code how ...