Tank full

Two hl of water were poured into a block-shaped tank with dimensions of 450 mm and 600 mm and a height of 900 mm. How many liters of water need to be added to keep the tank full?

Correct answer:

x =  43 l

Step-by-step explanation:

$$\begin{gathered} a=450\text{mm}\to \text{dm}=450:100\text{dm}=4.5\text{dm} \\ b=600\text{mm}\to \text{dm}=600:100\text{dm}=6\text{dm} \\ c=900\text{mm}\to \text{dm}=900:100\text{dm}=9\text{dm} \\ {V}_1=a\cdot b\cdot c=4.5\cdot 6\cdot 9=243\text{l} \\ {V}_2=2\text{hl}\to \text{l}=2\cdot 100\text{l}=200\text{l} \\ x=V_1-V_2=243-200=43\text{l} \end{gathered}$$

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