



 
Hi Curtis, Is this what you have in mind? The units are inches. 5 feet is 60 inches so the radius of the inside cylinder is 66/2 = 33 inches. The volume of a cylinder is π r^{2} h where r is the radius and h the height. The volume of dirt is the volume of a cylinder of radius 33 + 24 = 57 inches and height h inches minus the volume of a cylinder of radius 33 inches and height h inches, that is
But this is in cubic inches and you have the volume of dirt as 3.5 cubic yards. There are 36 inches in a yard and hence 36^{3} cubic inches in a cubic yard. Hence
Solve for h. Penny  


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