Silo

The outer perimeter of the silo is 10 m. The concrete wall is 13 cm thick. What is the diameter and area of the inside floor of the silo?

Final Answer:

d =  2.92 m
S =  6.71 m²

Step-by-step explanation:

$$\begin{gathered} o=10\text{m} \\ h=13\text{cm}\to \text{m}=13:100\text{m}=0.13\text{m} \\ o=2\pi r=\pi D \\ D=o/\pi =10/3.1416\doteq 3.1831\text{m} \\ d=D-2\cdot h=3.1831-2\cdot 0.13=2.92\text{m} \end{gathered}$$

$$\begin{gathered} r=d/2=2.9231/2\doteq 1.4615\text{m} \\ S=\pi \cdot r^2=3.1416\cdot 1.4615^2=6.71{\text{m}}^2 \end{gathered}$$

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