Four persons P, Q, R and S are in custody and one of them has committed a crime. They say:
P: Q did it.
Q: S did it.
R: I did not do it.
S: Q lied.
If exactly one of the statements is false, who is guilty?
Pick an option to check yourself, or open the answer below.
Show answer & explanation
Correct answer: B. Q
Explanation
Q's and S's statements contradict each other, so exactly one of them is false and P's and R's are true. P says Q did it, so Q is guilty (Q's claim is the false one).More Discrete Structures and Optimisation questions
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