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Questions tagged [liars]

Puzzles that focus on getting information from truth-tellers (who never lie), liars (who always lie), and Jokers (who answer at random).

4
votes
2answers
125 views

Liars, truth-tellers and jokers

In a strange village there are three kinds of persons: knights (always telling the truth), knaves (always lying) and jokers (who may either tell the truth or lie). A, B, C and D live in this village, ...
4
votes
1answer
169 views

Four Doors, One Escape

You are trapped in a room with four adjacent doors upon a wall. On each door is one of the first letters of the alphabet, in order, from left to right. You know that one of the doors leads to freedom, ...
7
votes
3answers
575 views

Three knights or knaves, three different hair colors

In a group of three people (A, B and C), everyone has a different hair color (blond, black or brown, not necessarily in this order) and everyone may be either a knight (always telling the truth) or a ...
42
votes
11answers
8k views

3 doors, three guards, one stone

You are in a room with three doors. You find out that behind two of these doors, the darkest pit of hell is waiting for you to make a mistake. The other door leads to heaven, where you obviously want ...
4
votes
1answer
330 views

Lying under arrest

I'm in a custody, under arrest, no contact with the outside world. I do not know if in that jurisdiction authorities are allowed to lie. Some real-world knowledge suggest lying by authorities is ...
3
votes
2answers
125 views

The truth within

Someone living in the remote cabin that you do put a virus onto your PC. Here are your suspects: Your brother, Liam, who only tells the truth about his opinions. Your sister, Irene, who tells the ...
18
votes
5answers
1k views

Island of Knights, Knaves and Spies

There is an island with $N$ inhabitants (for example $A_1, A_2, \dots, A_N$), each of them is either a knight, a knave, or a spy. As usual: knights will always tell the truth upon answering a ...
3
votes
5answers
349 views

A story about liars

Evelyn, Skylar, Alayna, Madelyn, Jonathon, Lara, Alyin, Felix, Iris, Bob and Roslina live on an island where some people always tell the truth, and the rest always lie. Roslina says "Alyin and Evelyn ...
10
votes
1answer
1k views

Island of Liars

A king goes to an island, where there are 5823 people who always tell the truth and 8723 who always lie. The king is special guest for the party celebrating 2053 year. On the party, liars and ...
48
votes
15answers
6k views

Find the identity of the four troll brothers

The four troll brothers Wudhor, Xhaqan, Yijlob and Zrowag have the following properties: Wudhor always says the truth. Xhaqan always lies. Yijlob lies or says the truth unpredictably. ...
87
votes
15answers
854k 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. One of the guards always tells ...
10
votes
3answers
11k views

Knights , Knaves and Spies - Part 1

I was working my way through some Knight and Knave Puzzles in Discrete Maths by Rosen, when I came across the following question: There are inhabitants of an island on which there are three kinds ...
34
votes
16answers
5k views

XKCD inspired logic puzzle

I came up with a logic puzzle inspired by this xkcd comic. I don't yet have an answer, and I am wondering if anyone can come up with one. You are in a room with three doors. Two of the doors lead ...
1
vote
2answers
298 views

Brain twister. A simple riddle to play [duplicate]

You are lost big crowded (monster). There are only two human living Jacobe and Recode . Your task is to reach your home, there are two routes and you are confused. Conditions: Jacobe always tell the ...
2
votes
2answers
72 views

Does it exist a way to solve visually by using a grid or to find the truth among a set of five people telling different statements?

I am having problems with trying to solve this riddle therefore I am looking for help. The situation is as follows: At a semiconductor laboratory in Hsinchu a security guard caught five ...
5
votes
6answers
628 views

You meet Yessayer, Nosayer, Truther, Liar

You meet 4 persons you haven't seen before, and must ask questions to determine who is who.They know each other, and their friends' behaviour. You may ask each as many times as you want but only yes/...
-1
votes
2answers
110 views

who eats more fruits? [closed]

in a party 3 brothers discussing: first brother says " I ate more fruit than 2nd brother and 2nd brother ate more fruit than 3rd brother" 2nd brother says " 3nd brother ate more than me also 3rd ...
6
votes
3answers
446 views

Monty's Labyrinth

(A fun combination of two classic puzzles, hope seasoned puzzlers enjoy.) Having escaped through almost all of a labyrinth, you are met by three magical doors. Two of them lead to certain and ...
6
votes
1answer
572 views

Classic two guards and two doors

I recently heard a version of the classic two guards (one is a knight who always tells the truth and the other is a knave who always lies) standing by two doors (one leads to certain death and the ...
3
votes
4answers
474 views

The Three Mystery People- An Actual Mystery

I believe almost everyone has heard this riddle before. There are three people in front of you. One always tells the truth, one always lies, and one answers randomly between truth and lies. You ...
4
votes
2answers
512 views

yes/no logic problem

There is a truth teller (always tells the truth), a liar (always lies), and one that sometimes answers truthfully and sometimes lies. Each person knows who is who. You may ask three yes or no ...
9
votes
1answer
690 views

Murder in the Royal Court

An entry in Fortnightly Topic Challenge #40: Retrograde Analysis! I can't believe it! Last night we heard a bit of fighting... but we had no idea that... our King was in check, and my fellow Rook and ...
6
votes
9answers
1k views

Five beautiful ladies

So there are five beautiful ladies whose faces are veiled. You can distinguish them well as they have written their (correct) names Alice, Betty, Cindy, Diana and Emily on their T-shirts. You know ...
6
votes
1answer
226 views

Truth tellers or liars among two people

Two guys, number One and number Two. You ask number One "Is there a truth-teller among you?". He replies and you have the answer to your question. What is number One and what is number Two?
3
votes
4answers
303 views

Classic 2 Guards But With 3 Doors Instead

So the rules are almost the same : You get to ask just one question to whichever guard you want to (just 1 guard; asking both guards is not allowed) There are 2 guards, one tells the truth and ...
2
votes
3answers
238 views

Fami-liar Situation

Exactly one of Sam or Tom has family visiting. They make these statements: Sam: "Tom has family visiting, but I don't." Tom: "Sam is lying, or I am lying, or possibly we're both lying." ...
5
votes
1answer
134 views

A Tournament to Remember

The King: Recently we had a big tournament, worth being immortalized in the chronicles of my kingdom. Unfortunately, the court scribe misplaced the record of the final event, and we need to restore it....
-4
votes
3answers
138 views

Riddle Again, Riddle Again, What am I? [closed]

1. If a chicken says, "All chickens are liars" is the chicken telling the truth? 2. A man is traveling to a town and comes to a fork in the road. If he goes left, he goes to the liars' village....
11
votes
3answers
690 views

A Space Station 13 complicated escape

After successfully resolving this tricky situation, you, the Captain of the Space Station 13, have ordered what remains of your crew to gather in the escape shuttle. Accompanied by the Security ...
6
votes
4answers
242 views

A Space Station 13 malfunctioning A.I

Disclaimer: It is not necessary to read the previous puzzle, or the one before even if it continues on the same story. The current puzzle is a different one which can work as a pure standalone. ...
6
votes
4answers
5k views

Which color shirt is Andrew wearing?

Andrew and Bob are talking to each other, but we don't yet know who is who. The guy in the blue shirt says, "I am Andrew." The guy in the red shirt says, "I am Bob." If at least one of them lied, ...
6
votes
3answers
744 views

How would one make a good liars puzzle?

I’ve seen and made a few liars puzzles, and a recurring theme with liars puzzles is that they can be too easy, and can be dull, perhaps a bit repetitive. How can you come up with a Liars puzzle that ...
1
vote
1answer
352 views

Tell the truth Puzzle [duplicate]

There are three people (Ajay, Bhuvi and Chandu), one of them is a Gun, one a missile, and one a robot. The Gun always tells the truth, the missile always lies, and the robot can either lie or tell the ...
23
votes
3answers
2k views

A Space Station 13 tricky situation

You are the Captain of the Space Station 13, and everything went bad very quickly. Most of the crew died, and it took you not so long to figure out that some people are not who they're supposed to be (...
4
votes
3answers
445 views

The Magical Prison Riddle

(I made up this riddle myself, hope you enjoy it) A criminal was using magic to flatten a building, while everyone, except 2 people, ran away being super scared. The police of magic came, and with ...
5
votes
2answers
1k views

The 3 Talking Hats

There are 3 talking hats on the table. Each can ask 2 questions, to either hat. 1 of them speaks only truth. 1 speaks only lies. 1 can speak only when spoken to, he will speak at random. YOU know who'...
1
vote
1answer
389 views

7 Prisoners Say

Prisoner 3 says: "Prisoner 5, Prisoner 6 and I are truthful". Prisoner 6 says: "Prisoner 5 and Prisoner 1 are truthful". Prisoner 4 says: "Prisoner 7 lies". Prisoner 1 says: "...
6
votes
5answers
1k views

Over the Bridge, If You Dare [closed]

A young man walks through the forest. He comes to a bridge. In front of the bridge is a large man carrying an axe. The man says, "If you want to cross this bridge, you must tell me something. If ...
8
votes
6answers
527 views

Eye exam for the truth-teller, liar and joker

A, B and C went for a eye exam together for their driver licenses. All 3 of them have bad eye sight and needed their own glasses to see clearly. However only 1 of them remembers to bring the glasses....
11
votes
8answers
10k views

Survive from death by asking the right question from trolls

You are in the intersection of two roads, there is a troll in the beginning of each road. One of them is liar (always lies), and one of them always tells the truth. One of the roads, ends to your ...
18
votes
4answers
2k views

On which day The Joker usually going on a date?

You are an investigator. You are to investigate The Joker to know on which day he usually goes on a date with Harley Quinn. The Inspector said that The Joker is lying if and only if it's Monday, ...
10
votes
3answers
2k views

Knights and liars

An island is inhabited by both Liars and Knights. Knight always tells the truth and Liar always lies. One day 12 islanders gathered together and issued a few statements. 2 of the islanders said "...
22
votes
6answers
10k views

Which teacher is the murderer?

In the first day of a new class semester, a student was murdered inside the classroom. No witnesses, no murder weapon, and no evidence. The police got four teachers as possible suspects, but they all ...
6
votes
5answers
28k views

Why does this answer to “two doors with two guards” work?

On this post: Two doors with two guards - one lies, one tells the truth the most common answer for this riddle is given. However, while the answer marked as correct is the most common solution I ...
1
vote
3answers
629 views

Who broke it. 3 person logic

D walks into a room and sees his computer is broken. He asks "Who broke my computer?". A says B did it B says A is lying C says he did not Of the three, it is known that only one is ...
3
votes
3answers
336 views

Who is the Culprit

One day you were at the hospital that you work at. You have 7 people you are over for their residency, since you are the head pediatric doctor. There was Ava, Ben, Chris, Delilah, Evan, Francine, and ...
11
votes
1answer
459 views

Einsteins knights and knaves

For an upcoming major puzzling event, I was honored with the task of creating one of the puzzles which will be presented. I decided to go with a variation of Einstein's puzzle. I selected four ...
6
votes
10answers
1k views

Knights and Knaves Puzzle

On the island of knights and knaves, one of the inhabitants says "If I am a knight, then I will eat my hat." Will the inhabitant eat his hat?
26
votes
6answers
5k views

Out of these 20 Doors, Which One Leads You to the Jackpot?

Congratulations for achieving this final stage of "Millionaire Super Logic" show! Once again, my name is Athin, and I'll be your host to help you win the jackpot of one, milLION, DOLLARS! *audience ...
10
votes
4answers
1k views

Meta Knights and Knaves Puzzle with Hats

I landed on the island of Knights and Knaves where Knights always tell the truth and Knaves always lie. I set out to find their two leaders, Raymond and Martin and I really wanted to talk with Martin....