Shown is the roof framing plan for a small, single story, st…

Shown is the roof framing plan for a small, single story, steel building.  The roof deck consists of sheets of steel decking that are 36 in. wide and 20 ft long, which must be lapped [s] in. on all sides.  Using the rows and columns methods and assuming that all cut remnants are waste, determine the number of sheets of steel decking needed for the roof.  Express your answer as a whole number of sheets.