Reference no: EM132281425

?Janson's Department Store in? Stark, Ohio, maintains a successful catalog sales department in which a clerk takes orders by telephone. If the clerk is occupied on one? line, incoming phone calls to the catalog department are answered automatically by a recording machine and asked to wait. As soon as the clerk is? free, the party who has waited the longest is transferred and serviced first. Calls come in at a rate of about 10 per hour. The clerk can take an order in an average of 3.0 minutes. Calls tend to follow a Poisson? distribution, and service times tend to be negative exponential.

The cost of the clerk is ?$10 per? hour, but because of lost goodwill and? sales, Janson's loses about ?$27 per hour of customer time spent waiting for the clerk to take an order.

Janson's is considering adding a second clerk to take calls. The ?store's cost would be the same ?$10 per hour. The total cost? (service cost +waiting ?cost) = ?$_______ per hour ?(round your response to two decimal?places).