Hectoliters of water

There are 942 hectoliters of water in a cylindrical tank with an inner diameter of 6 m. The water reaches two-thirds of the tank's depth. Calculate its depth.

Correct answer:

h =  2.2211 m

Step-by-step explanation:

$$\begin{gathered} D=6\text{m} \\ V=942\text{hl}\to {\text{m}}^3=942:10{\text{m}}^3=94.2{\text{m}}^3 \\ r=D/2=6/2=3\text{m} \\ {S}_1=\pi \cdot r^2=3.1416\cdot 3^2\doteq 28.2743\text{m} \\ V=S_1\cdot c \\ c=V/S_1=94.2/28.2743\doteq 3.3316\text{m} \\ h=\frac{2}{3}\cdot c=\frac{2}{3}\cdot 3.3316=2.2211\text{m} \end{gathered}$$

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