Discussion Forum

While I was entering defence Headquaters , I met three persons Lau, Nau and Pau.One among them always speaks truth , one always lies and the other alternates between truth and lie in any order.At least one among them knew the access code for high security areas.When I asked them about the code, their replies were as given below.Each of them made two statements.

Lau:Only one among us knows the code.

      Pau knows the code.

Nau:I dont know the code.

      : Lau knows the code.

Pau:Each one among us knows the code.

     :I know the code.

Who among them knows the code?

Answer:

Explanation:

Assuming both the statements of Lau are true, we get Pau knows the code.So, the second statement of Pau is true and his first statement must be wrong .So, both statements of Nau must be false, but the first statement happens to be true.

Assumingg both the statements of Nau are true.

Assuming Pau's both the statement are true.Both the statements of Lau or Nau cant be false, it violates the given conditions.