Answer:
362880
Step-by-step explanation:
Given that a sales representative must visit nine cities. There are direct air connections between each of the cities
Since there are direct connections between any two pairs the sales rep can visit in any order as he wishes.
He has 9 ways to select first city, now remaining cities are 8. He can visit any one in 8 ways.
i.e. No of ways of visiting 9 cities in any order = 9P9
= 9!
= 362880
So no of ways he visits the cities since there are direct connections between any two cities is
362880
