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Truth-Tellers and Liars

Time to play detective! Every puzzle in this collection contains a set of statements, but it's up to you to figure out which of those statements are true and which of them are false. See more

Level 2


John tells the truth on Mondays, Thursdays and Saturdays, but lies on every other day.

One day he said, “I will tell the truth tomorrow.”

On which day of the week did he make this statement?

Only one of the following statements is true. Which one?

1) Statement 2 is true.
2) Statement 5 is false.
3) All five statements are true.
4) All five statements are false.
5) Statement 1 is false.

Knights always tell the truth and Knaves always lie.

In a group of six people, the following statements are made:

  • Alice says, "None of us are Knights."
  • Bob says, "Exactly two of us are Knights."
  • Cathy says, "At least three of us are Knights."
  • Dave says, "At most three of us are Knights."
  • Evelyn says, "Exactly five of us are Knights."
  • Frank says, "Exactly one of us is a Knight."

How many Knights are there?

An island has only two types of people: Knights (who always speak the truth) and Knaves (who always lie).

I met two men who lived there and asked the taller man if they were both Knights. He replied, but from his answer, I could not figure out what type of person each man was, so I asked the shorter man if the taller man was a Knight. He replied, and after that I knew which type of person each man was.

Were the men Knights or Knaves?

On one side of the card it is written that
"The statement on the other side of this card is true"

And on the other side it is written that
"The statement on the other side of this card is false"

Which statements is/are true?


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