Two cousins were talking about their parents' safes. "They said I can keep my comic books in their safe, if I figure out the right combination, and enter it on the keypad correctly on my first attempt," said the first cousin. "I've listed out a lot of combinations but haven't figured out if I h...

An original riddle: My prefix is a type of car. My suffix means you can’t see far. My infix concerns the outside. Together, I remove the inside. What am I?

According to Wikipedia a mnemonic is "any learning technique that aids remembering". Here is a mnemonic sentence: Empty City, Green Dwarfs Can you tell what it is about? The answer is a six letter word.

You are given the fractions $\frac{4}{3}, \frac{7}{3}, \frac{10}{3}, \frac{13}{3}.$ Use any operation of $+, -, *, /, ()$ to build 28 with those four fractions. You must use all four fractions exactly once.

Here is a follow up of Building the perfect number 28 with fractions You are given the fractions $\frac{3}{2}, \frac{5}{2}, \frac{7}{2}, \frac{11}{2}.$ Use any operation of $+, -, *, /, ()$ to build 28 with those four fractions. You must use all four fractions exactly once.

As a whole, I am intense desire. Behead me, and I accommodate children. Behead me again, and I accommodate animals. Restore me, and I become fire. What am I? (An original riddle)

This post is not a puzzle. There is nothing puzzly hidden inside it or the self-answer, posted at the same time. Some research shows that there seems to be two types of Braille. Please help me explain it. EDIT: An even further research shows that the difference is largely punctuations.

I've tried finding any possible link between "desert" and "arrive" and had no success. I need to know.

I am working on a program to brute-force a LanLan Gear Octahedron I bought second-hand (and scrambled). I have no background in "cubing" and just fancied solving the problem. The structure comprises 8 "Centre" pieces (at the centre of each face); 6 "Corner" pieces; and 12 "Edge" pieces each hold...

I was impressing various students at my school by showing them various twisty puzzles when one of them recalled a puzzle they owned. I thought I might have seen it somewhere, but I may have been thinking about something else. He said it had some sort of gear mechanism, and was a two-by-two cube....

My prefix is man. My suffix is sharp. My infix is man. The whole is hard. What am I?

This is an original riddle. It may require some specific knowledge, but nothing that can't be easily acquired. ma(c + n + s) = ?

I have noticed that when adding a new question on Puzzle Stack Exchange (PSE), one may sometimes see the warning: The question you're asking appears subjective and is likely to be closed Similarly, when posting a puzzle that is concise, for example, like this one, one may see the error: ...

Here's the crossword: I call it "A Abuse"... You'll find out why. Made with a crossword maker lol

Lets say you start with a set of sequential numbers starting from 2, (so 2,3, or 2,3,4, or 2,3,4,5 etc). The end goal is to use identical basic math arithmetic (+, -, x, /) to all of these numbers, to have them end up them all being different prime numbers. The end prime numbers they become mus...