Sand pedestal

The pedestal under the giant billboard is a prism-shaped steel plate structure filled with sand. How much sand will it fit, and what is the area of the plates used? We can neglect their thickness. The dimensions are 1 m*4 m*90 cm.

Final Answer:

V =  3.6 m³
S =  17 m²

Step-by-step explanation:

$$\begin{gathered} a=1\text{m} \\ b=4\text{m} \\ c=90\text{cm}\to \text{m}=90:100\text{m}=0.9\text{m} \\ V=a\cdot b\cdot c=1\cdot 4\cdot 0.9=3.6{\text{m}}^3 \end{gathered}$$

$S=2\cdot (a\cdot b+b\cdot c+c\cdot a)=2\cdot (1\cdot 4+4\cdot 0.9+0.9\cdot 1)=17{\text{m}}^2$

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