3. Scaffolding is to be constructed on all faces of a six-story building in order for major masonry rehabilitation work to be performed. The exposed surface area of the exterior walls of the building has been estimated to be 432,000 sq. ft. Historical records of the company show that for this simple type of structure, the production rate for erecting scaffolding by one worker is 0.002 hours per square foot of building surface area. If 10 workers (working 8-hour days) are assigned to do the entire scaffolding erection, what duration (in working days)should be used for this activity?

Fig: 1