In how many ways can eight directors, the vice chairman and chairman of a firm be seated at a round table, if the chairman has to sit between the vice chairman and a director?
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In circular arrangements with fixed positions, treat one seat as fixed to avoid rotational duplicates.
Fix the chairman’s position. Vice chairman can be on either side (2 ways). Remaining 8 directors can be arranged in $8!$ ways around the table. Therefore, total arrangements = $2 \times 8!$.