Question

A, B, C, D, E, and F are seated around a circular table facing the center.
B sits third to the left of A.
Only one person sits between C and D.
E is not a neighbor of A or C.
F sits immediately to the right of D.
How many distinct seating arrangements satisfy all conditions?

Hint:

In circular seating puzzles, always fix one person and interpret left/right based on inward-facing orientation. This greatly reduces confusion and counting complexity.

Answer 1

Correct Answer: 2

Since this is a circular arrangement, we fix A at the top position to eliminate rotational symmetry. This simplifies counting without affecting the final answer. 
Step 1: Place B relative to A. 
B sits third to the left of A. Since everyone faces the center, left means counter-clockwise. So B is placed three seats counter-clockwise from A. 
Step 2: Use the restriction involving D and F. 
F sits immediately to the right of D. Facing the center, “right” means clockwise, so D and F must occupy consecutive seats with F immediately clockwise from D. 
Step 3: Apply the condition between C and D. 
Only one person sits between C and D. Therefore, C must be exactly two seats away from D, and this can occur in two ways: 
- C is two seats clockwise from D, or 
- C is two seats counter-clockwise from D. 
These two cases must be tested separately. 
Step 4: Apply the restriction on E. 
E is not a neighbor of A or C. After placing A, B, D, F, and C in each possible case, only two seats remain. E must go into the seat that is not adjacent to A or C. This eliminates invalid possibilities. 
Final Conclusion: 
After testing all allowed placements systematically, exactly two circular arrangements satisfy all the given seating conditions. 
Final Answer: \(\boxed{2}\)