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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).

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3
votes
2answers
2k views

Knights and Knaves Propositional Logic

I have a question regarding Knights and Knaves and logical proposition. If I want to solve the puzzle and I assume I have two kinds of citizens: Knights, who always tell the truth, and knaves, who ...
16
votes
1answer
587 views

Find the number from 10 statements

You are given the following ten statements and are asked to determine a particular number. At least one of statements 7 and 8 is true. This either is the first true or the first false ...
8
votes
4answers
1k views

Trick or Treating in Trutham-And-Ly

An entry in the 19th fortnightly challenge... Trutham-And-Ly, you may remember, is a small town in the north of Logistan. It is divided into two districts, Trutham and Ly, separated by a small stream....
0
votes
3answers
197 views

Confusing puzzle

So recently I came up with this puzzle/riddle that's really confusing me. So four people/Jokers are sitting at a table. Sometimes they tell the truth, sometimes they lie. My question is, which ...
33
votes
23answers
5k views

Unfortunately, you died [closed]

Your soul is on its way to the afterlife when suddenly you arrive in a room. You look around and notice six humanoids staring at you. You walk toward them and you can suddenly hear them talk between ...
-4
votes
3answers
152 views

Bias and the Liar [closed]

A cylindrical glass has water half its height Some say it's half full, while some say it's half empty But if Clair the liar mostly tell what's not right Will she say "it is full" or she'll say "it ...
-1
votes
5answers
488 views

The People Of Trutham-And-Ly

Here's an interesting variation on the classical liar puzzles: Trutham-and-Ly is a small town in the north of Logistan. It is divided into two districts, Trutham and Ly, separated by a small stream. ...
15
votes
9answers
3k views

Find the correct door!

This is my first puzzle but I hope it will work out well and that everyone can enjoy it. While trying to get out of a dungeon, you arrive in a circular room with 5 doors at equal distances from each ...
2
votes
3answers
708 views

How to find the treasure?

You are standing in a Heptagonal room (has seven sides). Each side of the heptagon has a closed door, totaling four white doors and three black doors. In front of each door is a guard. Four of the ...
14
votes
5answers
2k views

Testing a new liar type

I haven't seen this kind of liar type before, so here is a simple puzzle as a means for a trial run. In particular, I did check it myself, but with new mechanics it's easy to miss something (I hope I ...
4
votes
1answer
296 views

What is the right answer for this question, with 4 different conditions

I'm confused; what are the right answers for the following question under each of the 4 different conditions listed below? “Are you Lala, or lying today, but not both?” If you are Lala, and you ...
5
votes
5answers
513 views

Identify who is who between 3 persons who tell the truth and lie alternately

Dipsy tells the truth in 1 day and lies in the next day alternately. If today he tell the truth, tomorrow he will lying, 2 days later he will tell the truth, and so on. Lala tells the truth in 2 ...
16
votes
3answers
2k views

Star Puzzle: Determine which circles are True and which circles are False

A circle with number x means: “This circle is connected (straight line) to x circles with a true statement” This is valid only if the statement in the circle is True. If a circle is False, ...
7
votes
3answers
879 views

Trolls pretending to be Knights and Knaves

There are two Trolls, and each makes a statement. Troll 1 says "if we are cousins, then we are both knaves." Troll 2 says "we are cousins, or we are both knaves." Could both of the trolls be ...
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 ...
3
votes
3answers
190 views

Honeycomb structure statements (T/F)

2 1 1 3 0 2 1 Above honeycomb structure contains numbers. A number at each cell represent a statement. x : This cell is surrounded by x True statements. ...
6
votes
4answers
1k views

5x5 statement table

Statement table. 3 2 1 4 1 2 3 3 3 3 3 4 6 4 4 2 3 4 4 3 1 1 2 4 3 Above 5x5 table contains numbers. A number at each cell represent a statement. x : This ...
-3
votes
9answers
616 views

5 guards, 5 doors, and probability

1st Guard: Always lies all the time. 2nd Guard: Always tells the truth all the time. 3rd Guard: 75% probability of telling the truth. 4th Guard: 50% probability of telling the truth. 5th Guard: 25%...
7
votes
3answers
4k views

Determine which statements are True, and which statements are False

Determine which statements are True, and which statements are False There are 3 consecutive False statements This is The First True Statement There are equal numbers of True and False ...
5
votes
1answer
327 views

Three truth teller boys on an island

Each inhabitant of an island are either a truth teller who always speaks the truth, or a liar, who always speaks falsely. Three boys P, Q and R who live in that island, are each either a truth ...
-9
votes
1answer
201 views

A guy once said he lies. I still think what he really does [closed]

If a guy says "I'm a liar", what could we deduce from it? Is he a liar or not? let us say he isn't a liar, then his statement that he's a liar affirms that he is a liar. Let us say he is a liar ...
9
votes
4answers
2k views

I do not speak lies

A person was travelling in the middle of an empty road. As he walked, he saw five doors, with guards in front of each one. He had no other way of crossing the road. The first guard said, "If all ...
25
votes
10answers
4k views

Liar and the Truth teller with 6 inhabitants

There are two types of people on an island: truth tellers and liars. Truth tellers always tell the truth, while liars always lie. A foreigner meets six of the inhabitants, and asks each of them the ...
5
votes
4answers
3k views

How many of them are lying?

Here is a puzzle I am struggling to solve: Seven people are in an argument, but potentially some or all of them are liars. They give the following statements: Bob: "No one lies." Jennifer: ...
9
votes
3answers
592 views

Council of Magic, 5 years later - more spellcasters, more deception

Council of Magic - 5 Years Later: Five years ago, you managed to gain the support of the Council of Magic. However, now the King of Puzzlington needs their aid once again. As it worked last time, he ...
27
votes
5answers
1k views

Council of Magic - a palace of deceptive spellcasters

Council of Magic: The King of Puzzlington has sent you to a distant palace to gain the aid of the Council of Magic. As your luck would have it though, spellcasters are a tricky sort. There are 4 ...
8
votes
2answers
717 views

Knight, Knave, Magician

In your quest to escape a Magician's lair, you are greeted by 3 identical looking gatekeepers. You can only proceed after correctly identifying which one is which. The only trouble is, they can ...
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. ...
6
votes
5answers
34k 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 ...
17
votes
6answers
6k views

A death at a restaurant

You are a mafia leader and because of mysterious recent developments, you had to call the meeting of heads which is happening right now at your's cousin restaurant. The problem is, after the opening ...
35
votes
8answers
6k views

Who committed the crime?

A crime has been carried out by one person, there are 5 suspects. Each suspect is asked under polygraph who they think committed the crime. Their answers are as follows: Terry : It wasn't Carl, It ...
5
votes
2answers
636 views

Telling the truth

Atal said Sonia did it. Sonia said Kumar did it. kumar said George did it. George said that he didn't do it and Laloo confessed that he did it if Atal didn't do it. One of the five of them did it ...
17
votes
5answers
3k views

Statements that the deities True and False cannot say

You over exert yourself working on logic puzzles and die of exhaustion. You are awoken by the omniscient deities True and False. True only speaks true statements and False only speaks false statements....
9
votes
3answers
639 views

Thirteen people telling truths or lies

A: There are exactly 5 people telling truths, while others are telling lies. B: F tells lie. C: E tells lie. D: G tells lie. E: If D is telling truth, B is too. F: If E is telling lie, C is too. G: If ...
2
votes
3answers
941 views

Puzzle to find one good person [duplicate]

There are 15 people who may lie or say the truth(bad people) and 16 people who will always say the truth(good) . Suppose A- bad person , B-good person and C-bad person, when asked about A, B will say ...
10
votes
4answers
1k views

The two neighbouring islands

A puzzle was asked in a mental ability test. Arstil and Byzinte are two neighbouring islands in a far-off corner of the world. The natives of Arstil (the Arstillians) and the natives of Byzinte (...
5
votes
1answer
406 views

The truth and lie mess

There are two persons with special traits such that : One speaks only lies and no truth on Monday, Tuesday and Wednesday and all truth rest of the week. The other speaks only lies and no truth on ...
14
votes
2answers
2k views

A Race of Liars

You find yourself in a strange land where a race with five participants has just taken place. Each of the runners is a different age, and each either always tells the truth, always lies, or strictly ...
14
votes
6answers
3k views

To Tell The Truth

Four friends get together. One tells the truth all the time. One lies all the time. One tells the truth on odd-numbered days and lies on even-numbered days. One tells the truth on even-numbered days ...
10
votes
3answers
1k views

The Expedition Into The Ancient Cave

You are a archeologist and have taken 8 of your students on a expedition trip to a ancient cave to try and find ancient treasure. After you and your team entered the cave, you travel as a group ...
7
votes
1answer
3k views

Who are the truth-teller dwarves?

Infomation/Story Your prince is bewitched and asleep. You have to feed him the good apples (from the truth-teller dwarves) to save him. But be careful. Only the truth-teller dwarves, who only tell ...
19
votes
3answers
1k views

Edward and the seven imps' Game

Excerpt of “Manipulating the Fabric of Space” “Miscasting translocation spells can have many nasty consequences. The caster’s body could be warped or torn apart, his soul could be separated ...
15
votes
2answers
1k views

Town of liars and truth-tellers with eccentric mayor

There is a small town with a strange custom. Residents each own a single pebble, painted blue or red, which they always carry in their pockets. Those with blue pebbles always tell the truth, and those ...
6
votes
3answers
380 views

Democrats and Republicans in a Circle

There are $N$ democrats and $N$ republicans sitting in a circle. Each of these people is either always honest or always deceitful. It is known that the number of honest democrats is the same as the ...
5
votes
1answer
487 views

What is the best name for true-tellers, liars and normals

In the world exists a lot of puzzles based on variations of true-tellers, liars and normals (sometimes lies, sometimes not). There are plenty of names for these characters, for example see the ...
16
votes
6answers
4k views

99 doors to death!

You wake up in a small locked room of a huge castle. There are 100 doors, numbers 1 to 100, and you are to open one of them. Open the correct door, and the entire castle is yours to keep. Open any of ...
32
votes
9answers
9k views

Which offer is better?

You are to make a statement. Of these two offers you have to choose one; which one is more profitable to you, and why? If the statement is true, you get exactly 10 dollars. If the statement is false,...
21
votes
3answers
3k views

Ten Tricky Mathematicians

Somewhere on the Hyperbolic Plane, you encounter ten mathematicians. You know that some of them always tell the truth while the rest always lie. Each of them knows which of the others tell the truth ...
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, ...
7
votes
1answer
670 views

The Beautiful Ladies' Brothers

The ladies mentioned in Five beautiful ladies have five brothers: Adam, Bob, Charlie, David, and Edward. Three have hazel eyes and are honest; two have lime-colored eyes and always lie. You are ...