Equine Refresh, the only bar at a horse show, has one bartender making and serving drinks. The average arrival rate is one customer every 50 seconds, Poisson-distributed. The bartender can serve, on average, a customer every 48 seconds. Service times are Exponentially-distributed. Given these data, on average, what is the average waiting time in minutes? Round your answer to the closest whole number-do not show any decimal places.