"Published in Vacaville, California, USA"
A trench is 200 ft. long and 12 ft. deep, 8 ft. wide at the top and 4 ft. wide at the bottom. How many cubic yards of earth have been recovered?
Solution:
To illustrate the problem, it is better to draw the figure as follows
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| Photo by Math Principles in Everyday Life |
The area of the base which is the area of the cross section of a trapezoid prism is
Therefore, the volume of earth removed from a trench which is the volume of trapezoid prism is
