Water 62

The water tank filled with 1/5 of water is in the shape of a cuboid with a height of 80 cm and a base measuring 30 cm x 40 cm. What is the height of the water level in the tank?

Correct answer:

h =  16 cm

Step-by-step explanation:

$$\begin{gathered} a=30\text{cm} \\ b=40\text{cm} \\ c=80\text{cm} \\ {V}_1=a\cdot b\cdot c=30\cdot 40\cdot 80=96000{\text{cm}}^3 \\ {V}_2=\frac{1}{5}\cdot V_1=\frac{1}{5}\cdot 96000=\frac{1\cdot 96000}{5}=\frac{96000}{5}=19200{\text{cm}}^3 \\ {V}_2=a\cdot b\cdot h \\ h=\frac{V_2}{a\cdot b}=\frac{19200}{30\cdot 40}=16\text{cm} \end{gathered}$$

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