Binary Logic / Truth-Tellers

CAT కోసం Binary Logic / Truth-Tellers పై 2 సాధన ప్రశ్నలు, జవాబులతో

Shishya సాధన ప్రశ్నలు, AI తో రాసినవి. ప్రతి జవాబును ఒక ఆటోమేటిక్ రెండో తనిఖీ సరిచూసింది, మనిషి కాదు.

1. 1.In a group of four people—P, Q, R, and S—each person is either a truth-teller (always tells the truth) or a liar (always lies). P says, 'Q is a liar.' Q says, 'R and S are both liars.' R says, 'P is a truth-teller.' S says, 'Q is a truth-teller.' How many of them are truth-tellers?

   • (A)1
   • (B)2
   • (C)3
   • (D)0
   జవాబు, సాధన చూడండి

   జవాబు: (B) 2

   సాధన: Assume P is a truth-teller, then Q is a liar. Q being a liar means 'R and S both liars' is false, so at least one is a truth-teller. R says P is a truth-teller (true), so R is a truth-teller. S says Q is a truth-teller (false since Q is a liar), so S is a liar. Thus, P and R are truth-tellers (2 total).

   తప్పు తెలియజేయండి

2. 2.Four friends - P, Q, R, and S - made the following statements: P: 'Exactly one of us is lying.' Q: 'Exactly two of us are lying.' R: 'Exactly three of us are lying.' S: 'All of us are lying.' Who is/are telling the truth?

   • (A)Only P
   • (B)Only Q
   • (C)Only R
   • (D)Only S
   జవాబు, సాధన చూడండి

   జవాబు: (C) Only R

   సాధన: If R is truthful, then exactly three are lying (P, Q, S). Checking: P says 1 lying (false), Q says 2 lying (false), S says all lying (false). This is consistent; R is the only truth-teller.

   తప్పు తెలియజేయండి