The trench

Calculate how many cubic meters of soil needs to be removed from the excavation in the shape of an isosceles trapezoid, the top width is 3 meters, the lower width is 1.8 m, the depth of the excavation is 1 m, and the length is 20 m.

Correct answer:

V =  48 m³

Step-by-step explanation:

$$\begin{gathered} l=20\text{m} \\ a=3\text{m} \\ c=1.8\text{m} \\ h=1\text{m} \\ S=\frac{a+c}{2}\cdot h=\frac{3+1.8}{2}\cdot 1=\frac{12}{5}=2.4{\text{m}}^2 \\ V=S\cdot l=2.4\cdot 20=48{\text{m}}^3 \end{gathered}$$

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