Gravel is being dumped from a conveyor belt at a rate of 30 ft3/min, and its coarseness is such that it forms a pile in the shape of a cone whose base diameter and height are always equal. How fast is the height of the pile increasing when the pile is 15 ft high?

Answer 1

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www.jiskha.com/questions/434719/Gravel-is-being-dumped-from-a-conveyor-belt-at-a-rate-of-10-ft-3-min-It-forms-a