Three islanders—A, B, and C—are either Knights (who always tell the truth) or Knaves (who always lie). A says, 'B and I are both Knaves.' B says, 'C is a Knight.' C says, 'A and I are of different types.' What type is each islander?
A is a Knave, B is a Knight, and C is a Knight.
If A were a Knight, A's statement would mean A is a Knave, a contradiction. Thus A is a Knave. Because A is a Knave, A's claim that both A and B are Knaves is false, which means B must be a Knight. Since B is a Knight, B's statement that C is a Knight is true. Finally, C (Knight) and A (Knave) are indeed of different types, matching C's true statement.
About this riddle
Logic riddles give you a few facts and ask what must be true. List what you know, cross out what cannot be, and see what is left.
Difficulty: Hard. More like this: Logic riddles with answers or try Einstein's Logic Grid for a different kind of puzzle.
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