Royal Street is home to two poets that will craft a few verses for tourists looking for a unique memento of their trip to the Big Easy. Customers arrive at the poets' stand according to the Poisson distribution and the authorship (service) times are based on negative exponential distribution. The average customer service time is 7 minutes and the average time between the arrivals of successive customers is 4 minutes. Assume that customers equally divide themselves between the two poets.
What is the probability that there are no customers receiving (or waiting for) poetry?
• .16
• .33
• .07
• .66