Knights and Knaves: Judy, Carol, Eve, Frank, and Mallory

Verified— unique solution

knights knaves

On an island, every inhabitant is either a knight, who always tells the truth, or a knave, who always lies. You meet Judy, Carol, Eve, Frank, and Mallory. Judy says: "If I am a knight, then Frank is a knave." Carol says: "Eve is a knave." Frank says: "Eve is a knave." Mallory says: "Judy is a knight and Carol is a knave." The others say nothing. Who is a knight and who is a knave?

Hints

Hint 1

Hint 2

Hint 3

Solution

Commit an attempt to unseal the proof. Write your answer — right or wrong, thinking it through is the point.

Once you've worked out who is who: how many of the 5 inhabitants are knaves? Answer with the number.

Hints

Solution

Comments