Quandaries and Queries


I would like to know how many cubic yards are in the following;

20 ft wide x 80 ft long x 4 inches thick?

I am trying to figure out how much concrete I will need to pour for a driveway.





You should first change the dimensions to yards. There are 3 feet in a yard and 12 inches in a foot so the dimensions can be rewritten

width: 20 feet = 20/3 yards
length: 80 feet = 80/3 yards
thickness: 4 inches = 4/(12  3) yards

Thus the volume is

20/3 80/3 4/(12  3) = 19.75 cubic yards.



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