Cuboid-shaped 47321

The cuboid-shaped fire fighting tank is 6m long and twice as wide. What is the height of the tank if the firefighters fill the empty tank in 0.5 hours with a hose flow rate of 12 liters per second?

Correct answer:

c =  1.2 m

Step-by-step explanation:

$$\begin{gathered} a=6\text{m} \\ b=a/2=6/2=3\text{m} \\ Q=12\text{l}\to {\text{m}}^3=12:1000{\text{m}}^3=0.012{\text{m}}^3 \\ t=0.5\text{h}\to \text{s}=0.5\cdot 3600\text{s}=1800\text{s} \\ V=Q\cdot t=0.012\cdot 1800=\frac{108}{5}=21.6{\text{m}}^3 \\ V=a\cdot b\cdot c \\ c=V/(a\cdot b)=21.6/(6\cdot 3)=1.2\text{m} \end{gathered}$$

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