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Six people sit around a circular table.

Person A and B must not sit next to each other.

How many ways are there of seating them?

With 6 people around a circular table,

. . there are: . ways to seat them.

Duct-tape and together

. . Then we have 5 "people" to arrange: .

There are: . ways to seat them.

But the 5 "people" could be: .

Hence, there are: . ways that andadjacent.are

Therefore, there are: . ways in which and areadjacent.not