"A fast-food restaurant has a drive-through window and during peak lunch times can handle a maximum of 60 cars per hour with one person taking orders, assembling them, and acting as cashier. The average sale per order is $7.00. A proposal has been made to add two workers and divide the tasks among the three. One will take orders, the second will assemble them, and the third will act as cashier. With this system, it is estimated that 100 cars per hour can be serviced. Use productivity arguments to recommend whether or not to change the current system."