In Rome, tourists arrive at a historical monument
Chapter , Problem 12(choose chapter or problem)
In Rome, tourists arrive at a historical monument according to a Poisson process, on average, one every five minutes. There are guided tours that depart (a) whenever there is a group of 10 tourists waiting to take the tour, or (b) one hour has elapsed from the time the previous tour began. It is the policy of the Tourism Department that a tour will only run for less than 10 people if the last guided tour left one hour ago. If in any one hour period, there will always be tourists arriving to take the tour, find the expected value of the time between two consecutive tours.
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