Answer:
A) 720 possible itineraries
B) 0.5
Step-by-step explanation:
She visited 6 cities.
A)Now, to get the number of different itineraries that are possible, we will use n! = n(n-1)(n-2)(n-3)....
In this question, n is 6
Thus;
6! = 6 × 5 × 4 × 3 × 2 × 1 = 720
B) First of all, let's calculate the number of sample points in the sample space for the number of cities visited. Since we are told that she visits san francisco and Denver, we will fix the two cities to be constant. Thus, we will have 6 cities, but permutate 4 of them. Which means, we have;
Ns = P(6, 4) = 6!/(6 - 4)! = 360
Thus;
P(visits Denver before San Francisco) = Ns/number of different itineraries that are possible = 360/720 = 0.5