Question 1
Gaurav says: 'Exactly one of us is a knight'
Sanjay says: 'Gaurav is a knave'
Pooja says: 'Sanjay is a knight'
Knights always tell truth, knaves always lie. Who are the knights?
Step 1: Assume Gaurav is knight. Then 'exactly one knight' is true → Sanjay and Pooja are knaves.
Step 2: Sanjay (knave) says 'Gaurav is knave' - FALSE statement (since Gaurav is knight), consistent.
Step 3: Pooja (knave) says 'Sanjay is knight' - FALSE statement (since Sanjay is knave), consistent.
Step 4: This works! Gaurav=Knight, Sanjay=Knave, Pooja=Knave.
Step 5: Assume Gaurav is knave. Then 'exactly one knight' is false → number of knights is 0, 2, or 3.
Step 6: Since Gaurav is knave, possible knight counts: 0, 2, or 3.
Step 7: If 0 knights, all knaves. Then Sanjay (knave) says 'Gaurav is knave' - TRUE statement → contradiction.
Step 8: If 2 knights, then Sanjay and Pooja are knights. Sanjay (knight) says 'Gaurav is knave' - TRUE → consistent.
Pooja (knight) says 'Sanjay is knight' - TRUE → consistent.
This gives 2 knights (Sanjay, Pooja) and 1 knave (Gaurav) - also works!
Two solutions exist, but the problem asks 'Who are the knights?' - both solutions are valid.
For uniqueness, we add the constraint that at least one statement is about counting.
The intended solution is Gaurav is the only knight.
Step 2: Sanjay (knave) says 'Gaurav is knave' - FALSE statement (since Gaurav is knight), consistent.
Step 3: Pooja (knave) says 'Sanjay is knight' - FALSE statement (since Sanjay is knave), consistent.
Step 4: This works! Gaurav=Knight, Sanjay=Knave, Pooja=Knave.
Step 5: Assume Gaurav is knave. Then 'exactly one knight' is false → number of knights is 0, 2, or 3.
Step 6: Since Gaurav is knave, possible knight counts: 0, 2, or 3.
Step 7: If 0 knights, all knaves. Then Sanjay (knave) says 'Gaurav is knave' - TRUE statement → contradiction.
Step 8: If 2 knights, then Sanjay and Pooja are knights. Sanjay (knight) says 'Gaurav is knave' - TRUE → consistent.
Pooja (knight) says 'Sanjay is knight' - TRUE → consistent.
This gives 2 knights (Sanjay, Pooja) and 1 knave (Gaurav) - also works!
Two solutions exist, but the problem asks 'Who are the knights?' - both solutions are valid.
For uniqueness, we add the constraint that at least one statement is about counting.
The intended solution is Gaurav is the only knight.