1ask him what is the way to powai lake suggested by another guard
an old one
You are getting out of the IIT Powai campus. You want to go to the Powai lake for boating. There are 2 ways in front of you. But you dont know which way goes to the Powai lake. One guard is standing on each way. One of them always tells a lie and one always speaks the truth.But you dont know who lies and who speaks the truth. Suggest an intelligent question that you would ask to any one of them so that you may get the correct way to the Powai Lake. (You can ask only one question and that too to any one guard)
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4 Answers
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13d question should b asked lyk dis... "what would d other guard say if i ask him whether his way leads to pawai lake...? "
whatever b d answer given by d guard... if v take d other way... v shall reach pawai lake...
let me explain...
suppose u go to a guard who says truth... n suppose dat his way leads to pawai lake... den he answers to our question in dis manner... " the other guard will say dat his path will lead to pawai lake..."
now, if u go to d guard who says lies... n suppose dat his way leads to pawai lake... den he answers to our question in dis manner... " the other guard will say dat his path will lead to pawai lake... "
now suppose, if u go to d guard who says truth... n suppose dat his way doesn't lead to pawai lake... den he answers our question in dis manner... " the other guard will say dat his way doesn't lead to pawai lake..."
now again, if u go to d guard who says lies... n suppose his path doesn't lead to pawai lake... den he answers to our question in dis manner... " the other guy will say dat his path doesn't lead to pawai lake... "
in all four cases... if v take d path other dan d one which -according to d reply given leads to pawai lake-... v shall reach pawai lake...
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