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Three people on Kauai Island are named Alice, Bob, and Carol. At least one of them is a Knight, and at least one is a Knave. Exactly one of them has a prize.

They made the following statements:

- Alice: "Bob doesn’t have the prize."
- Bob: "I don’t have the prize."
- Carol: "I have the prize."

Using logic and a truth table, determine who has the prize.

Answer :

Answer: Alice has the prize

Step-by-step explanation:

[tex]\boxed{\begin{array}{c|c|c||l}\underline{Alice}&\underline{Bob}&\underline{Carol}&\underline{Prize}\\T&T&F&\text{Alice}\\T&F&F&\text{no possible answer}\\T&F&T&\text{no possible answer}\\F&T&T&\text{no possible answer}\\F&F&T&\text{no possible answer}\\F&T&F&\text{no possible answer}\end{array}}[/tex]

Line 1:

Alice: Bob doesn’t have the prize (T) ... either Alice or Carol

Bob: I don’t have the prize (T) ... either Alice or Carol

Carol: I have the prize (F) ... either Alice or Bob

Alice is true for all of them!

Line 2:

Alice: Bob doesn’t have the prize (T) ... either Alice or Carol

Bob: I don’t have the prize (F) ... Bob

Carol: I have the prize (F) ... either Alice or Bob

nobody satisfies all three statements.

Line 3:

Alice: Bob doesn’t have the prize (T) ... either Alice or Carol

Bob: I don’t have the prize (F) ... Bob

Carol: I have the prize (T) ... Carol

nobody satisfies all three statements.

Line 4:

Alice: Bob doesn’t have the prize (F) ... Bob

Bob: I don’t have the prize (T) ... either Alice or Carol

Carol: I have the prize (T) ... Carol

nobody satisfies all three statements.

Line 5:

Alice: Bob doesn’t have the prize (F) ... Bob

Bob: I don’t have the prize (F) ... Bob

Carol: I have the prize (T) ... Carol

nobody satisfies all three statements.

Line 6:

Alice: Bob doesn’t have the prize (F) ... Bob

Bob: I don’t have the prize (T) ... either Alice or Carol

Carol: I have the prize (F) ... either Alice or Bob

nobody satisfies all three statements.

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