A triangular shaped ditch

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Quandaries & Queries

I am planning on constructing a triangular shaped ditch the measures 550 meters in length, 6 meters wide at the surface, .3048 meters at the invert of the ditch and 2 meters deep.

How many cubic meters of material will have to be excavated to construct this ditch

Tim,

Cross sectional area is (L_top + L_base)*h/2 . Multiply this by length and get about 3500 cubic meters (a third significant figure cannot be justified.)

By the way, why is the surface of the ditch specified in metric & the bottom in imperial (.3406m is one foot, right?) Different jurisdictions?

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