The Wear ever Shoe Company is going to open a new branch at a mall, and company managers are attempting to determine how many salespeople to hire. Based on an analysis of mall traffic, the company estimates that customers will arrive at the store at the rate of 9 per hour (Poisson distributed), and from past experience at its other branches, the company knows that salespeople can serve an average of 6 customers per hour (Poisson distributed). How many salespeople should the company hire in order to maintain a company policy that on average a customer should have to wait for service no more than 30% of the time?