A: turn left
B: do not turn left
C: go straight
If only one among A, B and C is truthful, the traveller
Analyzing the Crossroads Logic Puzzle
This problem requires determining the correct path at a crossroads based on statements from three residents (A, B, C). The key condition is that exactly one resident is telling the truth.
Resident Statements
- Resident A: "turn left"
- Resident B: "do not turn left"
- Resident C: "go straight"
Evaluating Each Scenario
We must check each resident as the potential single truth-teller:
Scenario 1: Resident A is truthful.
- A is truthful: Direction is left.
- B must be lying: The statement "do not turn left" is false. This means the direction *is* left. (Consistent)
- C must be lying: The statement "go straight" is false. This means the direction is not straight (left or right). (Consistent)
- Outcome: If A is the only truth-teller, the direction is left.
Scenario 2: Resident B is truthful.
- B is truthful: Direction is not left (so, straight or right).
- A must be lying: The statement "turn left" is false. This means the direction is not left. (Consistent)
- C must be lying: The statement "go straight" is false. This means the direction is not straight (so, left or right).
- Combining Conditions: The direction must be "not left" (from B and A) AND "not straight" (from C). The only remaining option is right.
- Outcome: If B is the only truth-teller, the direction is right.
Scenario 3: Resident C is truthful.
- C is truthful: Direction is straight.
- A must be lying: The statement "turn left" is false. This means the direction is not left. (Consistent)
- B must be lying: The statement "do not turn left" is false. This means the direction *is* left.
- Contradiction: B lying implies turning left, but C being truthful implies going straight. This scenario is impossible.
- Outcome: C cannot be the only truth-teller.
Determining the Traveller's Choice
Since only Scenario 1 (A is truthful -> go left) and Scenario 2 (B is truthful -> go right) are logically possible, and we don't know which resident is the truthful one, the traveller cannot be certain of the correct direction.
Therefore, the traveller cannot decide between going left or right.
Important Questions from Puzzle (Notes)
- Seven boxes S, F, G, H, T and U are kept one over the other but not necessarily in the same order. Only two boxes are kept below S. Only one box is kept above U. Only one box is kept between U and B. G is kept immediately above F. T is kept at some place below H.
How many boxes are kept between H and G? - Seven boxes E, F, G, H, S, T and U are kept one over the other but not necessarily in the same order. H is kept immediately above E. T is kept immediately above U. Only F is kept above S. Only two boxes are kept above H. T is not kept at third position from the bottom.
How many boxes are kept between G and F? - Seven boxes E, F, G, H, S, T and U are kept one over the other but not necessarily in the same order. Only H is kept above E. Only T is kept between E and S. Only F is kept below U.
How many boxes are kept between G and F? Seven boxes E, F, G, H, S, T and U are kept one over the other but not necessarily in the same order. Only four boxes are kept between H and E. Only S is kept above H. Only two boxes are kept between F and U. T is kept immediately above G. U is not kept immediately above T. Which box is kept fourth from the top?
- Seven boxes E, F, G, H, S, T and U are kept one over the other but not necessarily in the same order. Only H is kept above E. Only T is kept between E and S. Only F is kept below U.
How many boxes are kept between G and F?
