192 questions
Filter by
Sorted by
Tagged with
1k views

### The Secret Agent Who Got Shot

You are a top secret agent trying to get into a enemy hide out. When you arrive at the enemy base, you see two guards at the door. You could take them out but that would make a ruckus and the enemies ...
3k views

### Cracking a 5 digit password

A gang of thieves has discovered that the 5 digit combination to a safe is even and has exactly one odd digit and exactly two digits equal to each other. How many possible combinations are there for ...
356 views

### A mysterious grid

Upon reaching the door to the office, instead of a normal keypad, you are presented with a strange grid. Tacked to the wall there is a punch-card with five columns, each column containing the numbers ...
185 views

### The spy who was killed

A spy tries to infiltrate into a Spanish base. In order to do so, he pinpointed a spot where he could listen the people outside of the gate who were asked to answer a short question. These questions ...
641 views

### Find the password in the grid

You are a spy sent to the Moon in the year 2025. Your mission is to infiltrate a base that is guarded by simply a single unique passcode of length <10 on a standard QWERTY keyboard. The only hint ...
361 views

### The Security to the Party [Part 38] [closed]

(This is a continuation of the series from last year. The first such question is found here) A party is being held at a local mansion. The host is very rich and his success is because of one thing ~ ...
2k views

### Find the 6-digit number encoded in this “mathematical” diagram

In the diagram below you can see four independent patterns. Each pattern is a puzzle by itself, and by solving it you will be able to encounter one or more digits of the final, 6-digit numeric ...
3k views

### End of the Maze

This the final installment of the Maze series. Here is Room 1 and here is the previous room. After you enter the answer from Room 5, you wait for the door to de materialize as usual, but nothing ...
1k views

### Room 5 of the Maze

This is Room 5 of the Maze series. For those wishing to start at the beginning, click here. To go back to the previous room, click here. As you arrive at the answer to Room 4, you realize it's the ...
1k views

### Room 4 of the Maze

This is Room 4 of the Maze series. For those wishing to start from the beginning, click here You wake up in Room 4 after a troubled night of 'sleep'. Your head was clouded all night with thoughts of ...
1k views

### Room 3 of the Maze

Exhausted from the effort of solving Room 2, you try to get a good night's sleep, but your sleep is interrupted by vivid dreams of fblthps, numbers, and vectors. The Maze is getting to you a bit, it ...
3k views

### Room 2 of the Maze

Still excited about your quick triumph over Room 1, you head straight for the suspended note and read it: Congratulations on making it through the warm-up to Room 2. From here on out, getting the ...
3k views

### Room 1 of the Maze

You wake up in a dark room that you don't recognize. The walls are made of some material you've never seen before. There is a door with a keypad next to it, and a small platform suspended in air in ...
1k views

It was a slow day at the office. Despite its name, Problem City was fairly quiet as of late. Joey was slowly melting into his chair when he recieved a phone call. Joey slowly swiveled his chair to ...
1k views

### Bicycle Lock Combination

My bicycle lock looks like this: This rebus helps me remember the combination: I read it left to right, top to bottom. What's the combination, and why?
771 views

### Doorknob's Revenge

Disclaimer: I'll be using the gender-neutral pronoun "xe" for the singular third person. After escaping from d'alar'cop's cellar, Doorknob♦ was understandably upset. After almost two months ...
2k views

### Find the two master lock combinations

Jeremy is a store owner. He uses combination locks like the one below at all of his store locations to secure cabinets of semi-important documents. Each combination is made up of 3 numbers, each ...
3k views

### The Secret Club (another one?!?)

Well... my first attempt to enter a Secret Club wasn't successful (see: The Secret Club), but this time I'm sure that nothing can stop me from reaching my goal... I've discovered this new club, whose ...
6k views

### The Secret Club

Since I was a kid, nobody wanted me in their super-exclusive clubs... the "House in the Tree Club"... the "Girls Only Club"... the "Whatever you are NOT Club"... but now that I am a skilled (and a bit ...
795 views

You are trying to crack someone's password. You don't have any password cracking software, nor do you have time to get any. From sources unknown, you know that: A. The password is alphanumeric (only ...
833 views

A famous mathematician was found on his deathbed this evening, leaving behind his lifes work trapped away on his computer. Protected by a password, it is believed this computer contains many ...
1k views

### What is the password to the diamond temple?

You are searching for the diamonds in a remote area. After hours, you see a temple with a diamond engraved. You realise that this is the diamond temple. The temple has the following also engraved: A ...
2k views

### Escape The Strange, Code-Filled Cave

You awake in a weird cave with something strange written on the wall. You find a small piece of paper on a rock. It says the following: Solving each code and entering it into the password entering ...
597 views

### Cracking the system

Months of preparation and coding has led you to this day. Slowly but surely you worked your way into the security of the most secure system in the world: the computer override for the vault containing ...
2k views

### Figure out the code

So remember all those puzzles about 100 or 1000 or however many logicians abducted by aliens and they are going to be killed if they can't figure out their hat color or the number on their back? Well ...
4k views

You work for a secret organization, and recently the personal data of a terrorist leader has fallen into your hands. This would be great news, except for the fact that all the files are locked with a ...
975 views

### A riddle by any other name

On his retirement, Bill Gates left behind a four number combination safe with a dial similar to this. In that safe is a secret that had eluded him many years ago...along with a small fortune of course....
2k views

### Five puzzles in one!

This is an experiment of nested puzzles. The answer of each puzzle is necessary to solve the next one. Sometimes you have to manipulate it, sometimes you have to open your eyes (and mind). Run, to ...
7k views

### Wife can't figure out husband's secret account password

John and Jane are married and keep a joint account at ABC Bank. They agreed that all of their income should go into the joint account. In early 2014, John started a new job at a software company, ...
601 views

### The Legacy of the Casino Owner - Code

So here's my first puzzle for you! A late casino owner leaves his descendants this letter: Dear my beloved sons Francis and Owen, dear my beloved wife Uma, The dice are rolled. You finally made it ...
357 views

### Seemingly random numbers and letters to satisfy a guard

A party is being held at yet another local mansion. The host is very rich and his success is because of one thing - his famous recipe for carbon nanotubes. He has pushed your tiny nanotube startup to ...
3k views

### What is my friend's PIN?

Just a fun Puzzle: My (fictive) friend told me his PIN: "My PIN is the highest 4 digit number that has the highest sum of unique differences." He explained: "my PIN consists of 4 numbers A B C D. ...
1k views

You have been trapped in a jail cell of an evil mastermind! The cell has a locked door with a keyboard with the letters a to z and an enter key. (Original image courtesy of Wikimedia Commons) The ...
2k views

### Should the angels play their game?

Two angels in heaven want to play a game. One of them comes up with an arbitrary, computable function from the integers to the integers. The other angel has to guess what it is. The second angel can ...
900 views

### Shortest Number Containing the Numbers 1-100?

Exactly what the title says: What is the shortest (fewest digits) number you can find such that somewhere in it, you can find each number 1- 100? My thinking for this puzzle is you have an electric ...
227 views

### The security to the party (Spaghetti's back!)

In celebration of catching the spaghetti thieves, a new party is being thrown! But the thieves have relatives who think they can do better! I wonder if they can. So they're hiding outside listening, ...
819 views

### An Exclusive Party

Your neighbour is hosting a party for a select group of people. . Hoping to get in, you hide in the front lawn and watch as guests begin to arrive. The first to walk up is a man, who says "Hi, I'm ...
3k views

### Find the password of the man's PC

A man locked his personal computer with a password and wrote some phrases in the hint box kept in his room. One day, his wife tries to login in his absence using the hints which contained the ...
2k views

### Pictures in the sand to satisfy a guard

A party is being held at a local mansion. The host is very rich and his success is because of one thing - his famous recipe for spaghetti. He has pushed your tiny spaghetti startup to the side, and ...
2k views

### Save d'alar'cop by Helping Him Defuse The Bomb Placed By An Assassin

d'alar'cop was busy solving puzzles and making riddles at his home. He heard a knocking on the door. He got up and reached the door to answer the knocking. Once he opened the door, no one was there. ...
857 views

### Poring Over the Numbers: A Hidden Message

I thank my lucky stars I'm able to write this to you. I spent a hefty percentage of my remaining cash at the courier's office and I want to underscore the importance of this communique. If a man comes ...
716 views

### You Force Heaven to be Ecstasy

You are Agent X, an enterprising NSA analyst who's been assigned the task of spying on Bill Krill, a US citizen suspected of unpatriotic opposition to warrantless NSA spying on American citizens. By ...
351 views

### The Broken Device

Your old friend from college is visiting and brings back this weird electronic machine with him. He says that it's supposed to take input and spit out a number, but some prank was pulled on him (he ...
452 views

### Computer Crisis Takeover! [Part 2!]

My last part 2 was sort of not a puzzle (oops) I've made sure this fits the criteria! This is part 2 of a series of multiple parts about a takeover of all the computers on earth. The links to ...
464 views

### The security to the party[#37] - Wish me “Happy birthday”!

A party is being held at a local mansion. The host is very rich and his success is because of one thing — his famous recipe for Spaghetti! The only guests that may attend are people who correctly ...
350 views

### I'll host my own party with.. (not sure if duplicate) [duplicate]

After not getting invited to any of the parties that have been going on lately I decided to make my own. As expected I hired my own security guards and sent out a letter to all the invited guests with ...
854 views

### The Security to the Party [Part 36] - an interesting one!

A party is being held at a local mansion. The host is very rich and her apparently miraculous success is entirely due to her famous recipe for spaghetti. A friend of yours gatecrashed one of the ...
533 views

### The Security to the Party [Part 34] [duplicate]

This is an easy one - a more interesting one is in the works! A party is being held at a local mansion. The host is very rich and his success is because of one thing - his famous recipe for spaghetti....