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UKMT Junior Mathematical Challenge, 2015

Combinatorics Difficulty 2.0 Junior Find the answer United Kingdom

Knave of Hearts: “I stole the tarts.” Knave of Clubs: “The Knave of Hearts is lying.” Knave of Diamonds: “The Knave of Clubs is lying.” Knave of Spades: “The Knave of Diamonds is lying.” How many of the four Knaves were telling the truth?

(A) $1$ (B) $2$ (C) $3$ (D) $4$ (E) more information needed

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