Frequent Questions
4,865 questions
248
votes
8
answers
30k
views
My prefix is food, my suffix is rude
I thought of this riddle myself. Feedback is appreciated.
My prefix is food.
My suffix is rude.
My infix comes in rounds.
I keep you off the ground.
What am I?
- 14.6k
27
votes
2
answers
3k
views
Around the World in Many Days
Deаr Puzzling,
How have you been? I am excited to tell you about my new trip. It’s my most ambitious one yet – a full trip around the world! I will definitely keep you posted about my whereabouts. I ...
- 83.9k
121
votes
1
answer
26k
views
Cryptic Clue Guide
This post is not a puzzle. There is nothing puzzly hidden inside it or the self-answer, posted at the same time.
What exactly is a cryptic crossword clue, and how do I write one?
- 156k
61
votes
4
answers
11k
views
Interview Question or Pathbreaking puzzle
I thought this changes the way series of numbers are looked at
1
1 1
2 1
1 2 1 1
Write down the next three lines
- 5,063
142
votes
16
answers
2.1m
views
Two doors with two guards - one lies, one tells the truth
You are a prisoner in a room with 2 doors and 2 guards. One of the doors will guide you to freedom and behind the other is a hangman–you don't know which is which, but the guards do know.
One of the ...
- 5,982
73
votes
7
answers
146k
views
Twelve balls and a scale
You are given twelve identical-looking balls and a two-sided scale. One of the balls is of a different weight, although you don't know whether it's lighter or heavier. How can you use just three ...
user88
49
votes
2
answers
4k
views
Vowelburger™ Riddle
(A new kind of riddle)
I ordered 5 Vowelburgers™ with buns and meat only - help me identify each one from the description on the menu!
Meat
Vowelburger™
A
weak
E
cyst
I
succeed
O
secured
Y
letter
- 10.5k
76
votes
1
answer
7k
views
Word Riddle - you love me or you hate me
With two I’m affirmative
With three I’m respectful
With four I’m more respectful
With all five I’m either loved or hated
But when I’m loved, I kill; and when I’m hated, I may save lives.
- 3,733
39
votes
2
answers
3k
views
Introducing Gladys, an intrepid globetrotter
Gladys has always led an active life full of adventure. As a retiree, she has a lot of free time on her hands and loves to spend it on her two favourite pastimes – travelling and crossword ...
- 83.9k
24
votes
3
answers
11k
views
A general solution to the decanting problem? (aka jug-pouring, water-pouring)
Take a look at these two questions:
- A Set of Water Jug Challenges
- Pouring problem
Now I'm asking for a generalised solution to that problem.
I define the problem as follows:
You are required ...
- 8,820
197
votes
26
answers
100k
views
In the 100 blue eyes problem - why is the oracle necessary?
The riddle
Randall Munroe (of xkcd fame) has, a bit hidden on his site, a logic puzzle:
A group of people with assorted eye colors live on an island. They are
all perfect logicians -- if a ...
- 2,300
41
votes
3
answers
4k
views
Determine the algorithm
So I was given this puzzle quite some time ago and just thought it would make a nice addition to this site:
Your task is to determine the method how the result is determined from the given number. A ...
- 2,466
34
votes
1
answer
4k
views
The first Density™ Puzzle!
Welcome to the very first puzzle in a new series! It's all about (hopefully) exploring new ways of creating puzzles, as densely as possible.
If you'd like to create your own Density™ puzzle, the ...
- 4,556
107
votes
7
answers
27k
views
Why does this solution guarantee that the prince knocks on the right door to find the princess?
I found this puzzle online:
On the top floor of a castle lives a princess. The floor has 17 bedrooms arranged in a row. Each bedroom has doors connecting to the adjoining bedrooms as well as to the ...
- 2,553
49
votes
6
answers
8k
views
Burning ropes as timers
You have 2 identical ropes which burn at a specific rate, and an unlimited supply of matches. When you light one end of a rope, the fire will take exactly 1 hour to travel to the other end of the rope....
- 3,543