Rain

The empty barrel with a radius of 8 dm and height of 1.2 m rain filled to 75% of its capacity. How many mm of water rained on the roof space of 75 m²

Final Answer:

x =  24.13 mm

Step-by-step explanation:

$$\begin{gathered} S=75{\text{m}}^2 \\ r=8\text{dm} \\ h=1.2\text{m}\to \text{dm}=1.2\cdot 10\text{dm}=12\text{dm} \\ q=75\%=\frac{75}{100}=\frac{3}{4}=0.75 \\ {V}_1=\pi \cdot r^2\cdot h=3.1416\cdot 8^2\cdot 12\doteq 2412.7432\text{l} \\ {V}_2=q\cdot V_1=0.75\cdot 2412.7432\doteq 1809.5574\text{l} \\ {V}_2=S\cdot x \\ x=V_2/S=1809.5574/75=24.13\text{mm} \end{gathered}$$

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