How many

How many m² of copper sheet is needed to replace the roof of a conical tower with a diameter of 13 meters and a height of 24 meters if we count 8% of the material for bending and waste?

Correct answer:

S =  548.3641 m²

Step-by-step explanation:

$$\begin{gathered} D=13\text{m} \\ h=24\text{m} \\ q=100\%+8\%=1+\frac{8}{100}=1.08 \\ r=D/2=13/2=\frac{13}{2}=6.5\text{m} \\ s=\sqrt{h^2+r^2}=\sqrt{24^2+6.5^2}\doteq 24.8646\text{m} \\ {S}_1=\pi \cdot r\cdot s=3.1416\cdot 6.5\cdot 24.8646\doteq 507.7446{\text{m}}^2 \\ S=q\cdot S_1=1.08\cdot 507.7446=548.3641{\text{m}}^2 \end{gathered}$$

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