Official Answer:We have five people (grocer, doctor, lawyer, tailor, barber) seated in a row with the following constraints:- The lawyer is at the right end of the row
- The grocer is immediately to the left of the lawyer
- The barber and tailor sit immediately next to each other
- The grocer does not wish to sit immediately next to the barber
From constraints 1 and 2, we can immediately determine:
- Position 4: Grocer (G)
- Position 5: Lawyer (L)
This gives us the partial arrangement:
_ _ _ G LThe remaining three people (doctor, barber, tailor) must occupy positions 1, 2, and 3.
From constraint 4: The grocer cannot sit next to the barber, so the barber cannot be in position 3 (which would be adjacent to the grocer in position 4).
From constraint 3: The barber and tailor must be adjacent to each other.
Since the barber cannot be in position 3, the barber must be in position 1 or 2.
Case 1: Barber in position 1
- Tailor must be in position 2 (to satisfy adjacency)
- Doctor must be in position 3
- Arrangement: B T D G L
Case 2: Barber in position 2
- Tailor can be in position 1 OR position 3 (both are adjacent to position 2)
- Sub-case 2a: T B D G L (tailor in position 1, doctor in position 3)
- Sub-case 2b: D B T G L (doctor in position 1, tailor in position 3)
All three arrangements satisfy the given constraints:
- B T D G L: ✓ All constraints met, doctor in middle
- T B D G L: ✓ All constraints met, doctor in middle
- D B T G L: ✓ All constraints met, tailor in middle
Since we have valid arrangements where either the
doctor or the
tailor could occupy the middle position (position 3), the identity of the person in the middle cannot be uniquely determined from the given information.
Answer: (D) Cannot be determined