Skip to main content

Questions tagged [real]

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

Filter by
Sorted by
Tagged with
129 votes
5 answers
142k views

Is this duplo train track under too much tension?

My kids were making this train track of duplo the other day, and this is what they put together. They are still very young, and for them, this is something big. They were really proud that they ...
Lezzup's user avatar
  • 6,396
83 votes
2 answers
4k views

A good puzzle is a double-edged sword

A rare double-edged sword is currently on loan from the British Museum to the Magna Carta exhibition. The sword itself is described as likely made in Germany around 1250-1330 and includes the ...
Richard's user avatar
  • 5,350
74 votes
8 answers
24k 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 ...
Emory Bell's user avatar
  • 1,907
74 votes
1 answer
20k views

Unsolved Mysteries: Kryptos

This is the second in a series of Unsolved Mysteries posts. These posts explore current unsolved real-world puzzles. Since these have been unsolved for years, it's uncertain whether anyone on on ...
GentlePurpleRain's user avatar
56 votes
22 answers
21k 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 ...
sousben's user avatar
  • 2,586
55 votes
1 answer
6k views

Unsolved Mysteries: D'Agapeyeff cipher

The D'Agapeyeff cipher is an as-yet unbroken cipher that appears in the first edition of "Codes and Ciphers", an elementary book on cryptography published by the cryptographer Alexander D'Agapeyeff in ...
pacosta's user avatar
  • 691
42 votes
1 answer
12k views

The Beale Papers

The background to this one's given here. NB: These may not be a genuine cryptograms (current thinking is that these are gibberish); but I though it interesting to share these in case they're genuine/...
JohnLBevan's user avatar
  • 1,305
40 votes
6 answers
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 ...
Tyler Seacrest's user avatar
37 votes
1 answer
921 views

Computations of an old woman

Recently I met a Polish woman who showed me something very interesting. Apparently her mother kept notebooks which she filled with strange calculations, never telling anyone what they were for. From ...
Jack M's user avatar
  • 997
36 votes
3 answers
3k views

Is this more than a packing puzzle?

I bought this set of wooden blocks at a garage sale today, and although it was a challenge to fit them in the box, I suspected they were more than just a packing puzzle. Can you guess what else they ...
Don Kirkby's user avatar
  • 2,602
36 votes
3 answers
4k views

Unsolved Mysteries: Magic Square of Squares

This is the first in what will hopefully be a series of Unsolved Mysteries posts. Note that this puzzle has no known solution, nor any proof that a solution is impossible. We will see how ...
GentlePurpleRain's user avatar
35 votes
4 answers
1k views

Which duplo digit is 6 or 9?

Not every question has to be as hard as possible, here is an easy one. I joined my kids playing with duplo, and found out that the duplo 9 and 6 look exactly the same if you turn one of them 180 ...
Lezzup's user avatar
  • 6,396
32 votes
9 answers
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 ...
athin's user avatar
  • 34.2k
31 votes
1 answer
3k views

Goodbye grand mother <3

My grand-mother died the 17th of June 20 from cancer after spending the last three months nearly alone in her house because of the COVID Pandemic. I dedicate her this puzzle. She's Lao and today, for ...
JKHA's user avatar
  • 6,033
29 votes
2 answers
7k 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 ...
hazoriz's user avatar
  • 393
27 votes
6 answers
16k views

Cut a cake into 3 equal portions with only a knife

You have to determine a way to cut a circular cake into exactly three portions of equal size. The only marking on the cake is a candle in the very center. All you have to work with is a knife that is ...
Rorxor's user avatar
  • 381
26 votes
4 answers
4k views

The "Loop of rope" dilemma

It's a "dilemma" that I encountered in real life problems. I believe that it's not new and is quite easy to explain, but may look puzzling at first glance. Alice and Bob are playing with a ...
WhatsUp's user avatar
  • 7,397
26 votes
1 answer
2k views

Real life puzzle: Unknown alphabet or shorthand

User JellicleCat posted this on linguistics stackexhange a few years ago. None of us were able to come up with a satisfying answer but most seemed to agree that it was an idiosyncratic cipher or ...
cyco130's user avatar
  • 361
26 votes
14 answers
2k 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, ...
KeyboardWielder's user avatar
26 votes
3 answers
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, ...
Ovi's user avatar
  • 403
25 votes
14 answers
14k 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 ...
user's user avatar
  • 1,047
25 votes
5 answers
2k views

Colouring a rug

I have a rectangular rug in my living room composed of coloured patches (shown below). For convenience I have labelled each distinct colour from 1 to 6. Let's suppose that it was created by starting ...
Dmitry Kamenetsky's user avatar
25 votes
1 answer
2k 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. ...
Mark Green's user avatar
22 votes
11 answers
5k views

Why is the pavement wet?

Saw this the other day. So I took this picture. There was another nearly identical wet patch 2 spaces away. Why is the pavement wet? Note: This is a straight forward physics puzzle. This is a ...
John's user avatar
  • 371
21 votes
11 answers
4k views

What's wrong with this line in a baking recipe book?

A cookie-baking recipe book (this one, specifically) has the following instruction in it, which is incorrect in a single spot: If you have a fan-assisted oven, you will need to reduce the recipe ...
user avatar
21 votes
2 answers
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: Once ...
Rand al'Thor's user avatar
21 votes
1 answer
3k 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 ...
Beastly Gerbil's user avatar
20 votes
5 answers
2k views

The Greenhouse Problem

While I was playing a certain popular indie farming game, I came across a dilemma. I have a greenhouse that I'd like to fill as efficiently as possible. How many plants can I fit in the greenhouse? ...
Nilster's user avatar
  • 874
20 votes
10 answers
4k views

What did I photograph?

What did I capture in these photos and how did it happen? This is straight from my camera without any edits or filters. Hint 1: Hint 2: Hint 3:
Dmitry Kamenetsky's user avatar
20 votes
3 answers
1k views

Early 1900's Paper Puzzle - Release the Key and Live Forever

This puzzle was found in an old attic and was a religious invitation. Release the key and you could send it in to receive a Bible based book. Apparently 1000's were made but I can find no more other ...
Eric Lang's user avatar
  • 203
19 votes
6 answers
5k views

The falling broom handle

As the reaction to my previous physics puzzle was somewhat mixed, I'll try again. I found this in an online physics book. You hold a broom as shown in the following picture: The head of the broom is ...
Jaap Scherphuis's user avatar
19 votes
1 answer
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'...
Mr Pie's user avatar
  • 6,682
18 votes
10 answers
2k 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 ...
humn's user avatar
  • 21.9k
18 votes
3 answers
3k views

Explain this bad parking job

One bright Monday morning, I drove to work and parked my car in Lot A. That morning, others also parked in Lot A, and we all found each other’s parking jobs to be satisfactory. That afternoon, a co-...
FlanMan's user avatar
  • 5,742
18 votes
2 answers
1k views

Reversical Engineerimicating

Ok, like, OMG!, this is totally true. I was looking through an old Notepad++ file I had and saw the following statements, verbatim, as I found them: ...
Chowzen's user avatar
  • 25.7k
18 votes
0 answers
694 views

Determining the meaning of a challenge coin

I saw this rather cool looking challenge coin the other day, and I was wondering what the associated binary on the back of it means, as it isn't standard ASCII. In plaintext: ...
DeepS1X's user avatar
  • 281
16 votes
4 answers
4k views

Is there a secret message in the first decimals of PI?

Is there a secret message encoded in the first decimals of $\pi$? Source: Vi Hart
Bass's user avatar
  • 77.6k
15 votes
6 answers
2k views

Pulling Apart a Jigsaw Puzzle

Assume you have a jigsaw puzzle that is also a tessellation. This means every piece has an identical shape and can be assembled into a 2D pattern that fills the plane with no gaps. Such a jigsaw ...
Skosh's user avatar
  • 3,818
15 votes
5 answers
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 ...
greenturtle3141's user avatar
15 votes
1 answer
634 views

Explain this holiday calendar oddity

Happy Boxing Day! Yesterday was Christmas Day, and in a few days, it will be New Year's Day. Each holiday season, those two holidays are always on the same day of the week (in this case, Friday). But ...
FlanMan's user avatar
  • 5,742
15 votes
3 answers
806 views

Reconstructing World Cup results

In the group stage of the World Cup, teams compete within eight groups of four teams each. Each group plays a round-robin tournament, in which each team plays three matches, one against each other ...
A. Rex's user avatar
  • 955
13 votes
4 answers
599 views

This number sequence has entered my life recently

Just recently, I've noticed this sequence of numbers has become a pretty big part of my life. It goes like this: 1, 2, 4, 6, 9, 12 So here's the mystery: What is this sequence? Where do I keep seeing ...
AJFaraday's user avatar
  • 628
13 votes
1 answer
1k 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. ...
Willtech's user avatar
  • 369
12 votes
21 answers
905 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 ...
Gabriel Burns's user avatar
12 votes
3 answers
1k views

Day and night of the two timers

            Make a non - 24 - hour day /  night cycle       &...
humn's user avatar
  • 21.9k
11 votes
1 answer
789 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 ...
Hashbrowns's user avatar
11 votes
1 answer
385 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 ...
ttaaoossuuuu's user avatar
11 votes
1 answer
418 views

Cryptic images have been posted around University of Central Florida campus. Can you help crack the cipher?

Recently there have been sightings of images duct-taped to various poles and such, reminiscent of a large house with windows within the UCF campus. On closer inspection, there is obviously a cryptic ...
forget me not's user avatar
10 votes
4 answers
2k views

A strange construction of locks

This gate is locked with 6 locks. What is the purpose of this construction?
Dmitry Kamenetsky's user avatar
10 votes
3 answers
753 views

Optimal refueling strategy

On the way home from work, I want to refuel my car. There are 5 petrol stations along the way that all have a different price for petrol. I know that the prices will be in the range [A, B], chosen ...
Dmitry Kamenetsky's user avatar