Answer:
The answer is 5,040.
There are 5,040 different possible itineraries.
Explanation:
The number of different possible itineraries equals the number of the selection of 7 cities from a total of 7 cities where order is important.
We solve thus:
[tex]N = P^{7}_{7} = \frac{7!}{(7 - 7)!}[/tex]
  [tex]= \frac{7!}{0!}[/tex]
  [tex]= 7![/tex]
  [tex]= 7 X 6 X 5 X 4 X 3 X 2 X 1[/tex]
  [tex]= 5,040[/tex]