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Sharpen your deduction skills with a variety of puzzles, ranging from basic reasoning up to some serious mind-benders. See more

Suppose you are visiting an island with knights, who always tell the truth, and knaves, who always lie.

You come across two islanders named Arnav and Bella.

Arnav says, "Bella is a knave."

Bella says, "Arnav is a knave."

How many of them are knights?

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Suppose I make the claim:

\[ \color{purple} { \text{If it's raining, I have my umbrella.} } \]

If I am **lying**, which of these must be the case?

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You are in a dungeon and come across three doors; one contains a treasure, and the other two lead to bottomless pits.

The doors have signs. You know the door that leads to treasure has a sign that is **false** and the other signs are **true**.

Which door should you take to get the treasure? (**Remember, the sign on the door that has the treasure is false.**)

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\[ \text{This statement is false.} \]

Is the sentence above a logical contradiction?

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