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

Concept

In a linear arrangement where everyone faces north, treat the row as fixed positions numbered from the left end. For a north-facing person, their LEFT is toward the lower-numbered (west) end and their RIGHT is toward the higher-numbered (east) end. "X sits k-th to the right of Y" fixes a directed gap (position of X = position of Y + k), while "m persons sit between X and Y" fixes only the size of the gap |posX - posY| = m + 1, not the direction. The strategy is to anchor the absolute clues (the end constraints) first, then place the directed clues, and finally the symmetric (between) clues.

Building the row

1. "No one sits to the left of F" makes F the left end, so F is at position 1.

2. "As many persons sit to the left of F as to the right of C": F has 0 persons to its left, so C has 0 persons to its right, i.e. C is the right end.

3. "D sits fifth to the left of C" gives position of D = position of C - 5.

4. "Persons between D and C is one more than persons between D and F": between D and C there are 5 - 1 = 4 persons, so between D and F there are 3 persons, i.e. |posD - posF| = 4. With F at position 1, D is at position 5, which forces C at position 10 (D + 5). The row therefore has 10 seats.

5. "C sits second to the right of B" gives B at position 10 - 2 = 8. "Three persons between A and B" gives a gap of 4, and the only seat available is position 4, so A is at position 4.

6. "Two persons between D and E" gives a gap of 3 from D (position 5); position 8 is taken by B, so E is at position 2.

7. "Position of A with respect to F is the same as position of C with respect to G": A is 3 seats right of F (4 - 1), so C must be 3 seats right of G, giving G at position 10 - 3 = 7.

Final arrangement (left to right)

F (1), E (2), _ (3), A (4), D (5), _ (6), G (7), B (8), _ (9), C (10).

Answer

E is at position 2 and G is at position 7, so the persons between them sit at positions 3, 4, 5 and 6 — that is 4 persons.

Cross-check

Re-reading the clues against the row: C - B = 10 - 8 = 2 (second to right), C - D = 5 (fifth to left), gap A-B = 4 (three between), gap D-E = 3 (two between), F at the left end with C at the right end (equal counts of 0), and A-F = C-G = 3. Every clue holds, so the arrangement is unique.