Cylindrical 28331

How many crowns will the paint cost to paint a cylindrical container (d = 4.2 m, h = 5.5 m) when about 5 m² of paint is painted from 1 kg of color, and 1 kg of paint costs 115 CZK?

Correct answer:

x =  2306.43 kc

Step-by-step explanation:

$$\begin{gathered} d=4.2\text{m} \\ v=5.5\text{m} \\ r=d/2=4.2/2=\frac{21}{10}=2.1\text{m} \\ {S}_1=\pi \cdot r^2=3.1416\cdot 2.1^2\doteq 13.8544{\text{m}}^2 \\ {S}_2=2\pi \cdot r\cdot v=2\cdot 3.1416\cdot 2.1\cdot 5.5\doteq 72.5708{\text{m}}^2 \\ S=2\cdot S_1+S_2=2\cdot 13.8544+72.5708\doteq 100.2796{\text{m}}^2 \\ c=115/5=23{\text{Kc/m}}^2 \\ x=S\cdot c=100.2796\cdot 23=2306.43\text{kc} \end{gathered}$$

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