A website manager has noticed that during the evening hours, about 3 people per minute check out from their shopping cart and make an online purchase. She believes that each purchase is independent of the others.
a) What model might you suggest to model the number of purchases per minute?
b) What model would you use to model the time between events?
c) What is the mean time between purchases?
d) What is the probability that the time to the next purchase will be between 1 and 2 minutes?