Question

Seven person wearing medals with numbers 1.2.3.4.5.6.7 are seated on 7 chairs around a circular table. In how many ways can they be seated so
that no two persons whose medals have consecutive numbers are seated next to each other? (Two arrangements obtained by rotation around the
table are considered different)
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Answer 1

Answer:

7 men can be sit at a round table in (7−1)!=6! ways. Since there is no distinction between clockwise and anticlockwise arrangements, the required number of arrangements is

2

6!

=

2

720

=360