A tank open at the top is made of sheet iron 1 inch thick. The internal dimensions of the tank are 4ft. 8in. long ; 3ft. 6in. wide ; 4ft. 4in. deep. Find the weight of the tank when empty and find the weight when full of salt water.(salt water weighs 64 lbs/ft³ and iron is 7.2 times as heavy as salt water).



For internal volume: Vi = (4)(8/12) (3)(6/12)(4)(4/12) Vi = 70.77 ft 3 External bolume: v= (4)(4/10) (3)(8/12) (4)(5/12) V= 78.273 ft3 Weight of empty tank: 7.495ft 3 (7.2)(64)(lb/ft3) 34,529 lb