Reservoir 43821

The reservoir has the shape of a sphere with a diameter of 14 m.

a) How many hectoliters (hl) of water can it hold?
b) How many kg of paint is needed to paint the reservoir if it is painted three times and one kg of paint is enough to paint about 9 m²?

Correct answer:

m =  205.2507 kg

Step-by-step explanation:

$$\begin{gathered} D=14\text{m} \\ h=9{\text{m}}^2\text{/kg} \\ n=3 \\ r=D/2=14/2=7\text{m} \\ S=4\pi \cdot r^2=4\cdot 3.1416\cdot 7^2\doteq 615.7522{\text{m}}^2 \\ m=n\cdot S/h=3\cdot 615.7522/9=205.2507\text{kg} \end{gathered}$$

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