Church roof 2

The roof has the shape of a rotating cone shell with a base diameter of 6 m and a height of 2.5 m. How much money (CZK) will cost the roof cover sheet if 1 m² of metal sheet costs 152 CZK and if you need 15% extra for joints, overlays, and waste?

Correct answer:

x =  6433.5026 Kc

Step-by-step explanation:

$$\begin{gathered} D=6\text{m} \\ r=D/2=6/2=3\text{m} \\ h=2.5\text{m} \\ s=\sqrt{r^2+h^2}=\sqrt{3^2+2.5^2}\doteq 3.9051\text{m} \\ S=\pi \cdot r\cdot s=3.1416\cdot 3\cdot 3.9051\doteq 36.8049{\text{m}}^2 \\ x=152\cdot 1.15\cdot S=152\cdot 1.15\cdot 36.8049=6433.5026\text{Kc} \end{gathered}$$

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