Question

Inspector arrested three persons- Kalia, Raza, Shera - on suspicion, in a theft case. It was found the one among these three was the thief. During the interrogation their replies were as follows. Kalia: I am not the thief. Raza is the thief. Raza: I am not the thief. Either Kalia or Shera is the thief. Shera: I am not the thief. Raza is not the thief.

If exactly one person among them always speaks the truth, another always speaks lies and the third alternates between the truth and lies, then who is the thief?

Accepted Answer

C. Test hypothesis: Raza is the thief. - Kalia's statements: "I am not thief" (True), "Raza is thief" (True) $\rightarrow$ Kalia always speaks Truth. - Raza's statements: "I am not thief" (False), "Kalia or Shera is thief" (False) $\rightarrow$ Raza always speaks Lies. - Shera's statements: "I am not thief" (True), "Raza is not thief" (False) $\rightarrow$ Shera alternates (T, F). This perfectly satisfies all conditions. Thus, Raza is the thief.

Truth and lie teller puzzle

Explanation

Practise this under exam conditions