The manager of the order-distribution center for Northwoods Backpackers has a company directive to downsize his operation. He has decided to conduct work sampling studies of employees in the order-processing department, the warehouse area, and the packaging area. In the warehouse area he has 17 employees who locate items, pull them, and put them on conveyors to the packaging area. A work sampling study was conducted over a five-day period to determine the proportions of time warehouse employees were idle, and out of the 50 random observations, 400 employees were idle.
a. How many observations should be taken if the manager wants to be 90% confident the estimate is within ±5% f the actual proportion of time a warehouse employee is idle?
b. The manager also conducted a work sampling study of the packaging area and discovered that the 28 employees were idle approximately 37% of the time. How might the manager redesign his operation to downsize and be more efficient?