Read the given instructions carefully and answer the questions: A certain…

Concept

In a single-row arrangement, fix positions by first locking any clue that names an absolute edge ("no one sits to the left" = leftmost seat; "as many to the left of X as to the right of Y" can force an edge). Then translate every "k-th to the right/left" and "m persons sit between" clue into a fixed gap (k seats apart, or m+1 seats apart) and place people one anchor at a time, extending the row only as far as the clues require. The total head-count is just the span from the leftmost to the rightmost occupied seat.

Application

Facing north, a person's left is the lower-numbered seat and right is the higher-numbered seat. Number seats 1, 2, 3 ... from left to right.

1. Edges. "No one sits to the left of F" puts F at seat 1 (leftmost). "As many persons sit to the left of F as to the right of C": there are 0 seats left of F, so 0 seats lie right of C — C is the rightmost person.

2. Chain B → C → D. C is 2nd to the right of B, so B is 2 seats left of C. D is 5th to the left of C, so D is 5 seats left of C. Writing C at the far right, B sits at C−2 and D at C−5.

3. Use the "between" balance. Persons between D and C is one more than persons between D and F. With D five seats left of C there are 4 people strictly between D and C, so there must be 3 between D and F — i.e. F is 4 seats left of D. Since F is seat 1 and D = C−5, this forces C = seat 10 (because D = seat 5 leaves exactly seats 2,3,4 between F and D).

4. Place A. Three persons sit between A and B, so A and B are 4 seats apart. B is at seat 8, so A is at seat 4 (seat 12 would fall outside the row). A is therefore 3 seats to the right of F.

5. Place E and G. Two persons sit between D and E → D and E are 3 seats apart; with D at seat 5, E lands at seat 2. "Position of A with respect to F equals position of C with respect to G": A is 3 to the right of F, so C must be 3 to the right of G, putting G at seat 7.

Final row (seats 1–10): F, E, _, A, D, _, G, B, _, C.

Cross-check

• Between A(4) and B(8): seats 5,6,7 → 3 persons. ✓

• Between D(5) and C(10): seats 6,7,8,9 → 4; between D(5) and F(1): seats 2,3,4 → 3; 4 = 3 + 1. ✓

• Between D(5) and E(2): seats 3,4 → 2 persons. ✓

• F is leftmost and C is rightmost, so 0 people lie left of F and 0 right of C. ✓

The row spans seats 1 to 10, so 10 persons sit in the row.