Dimensions of glass

An aquarium has dimensions of 64 × 50 × 45 cm and is filled to 5 cm below the upper edge. How many liters of water are in an aquarium? How many square meters of glass are needed to produce an aquarium?

Final Answer:

x =  128 l
S =  134.6 dm²

Step-by-step explanation:

$$\begin{gathered} a=64\text{cm}\to \text{dm}=64:10\text{dm}=6.4\text{dm} \\ b=50\text{cm}\to \text{dm}=50:10\text{dm}=5\text{dm} \\ c=45\text{cm}\to \text{dm}=45:10\text{dm}=4.5\text{dm} \\ {c}_2=5\text{cm}\to \text{dm}=5:10\text{dm}=0.5\text{dm} \\ V=a\cdot b\cdot (c-c_2)=6.4\cdot 5\cdot (4.5-0.5)=128{\text{dm}}^3 \\ x=V\to \text{l}=V\cdot 1\text{l}=128\cdot 1\text{l}=128\text{l}=128\text{l} \end{gathered}$$

$S=a\cdot b+c\cdot (2\cdot a+2\cdot b)=6.4\cdot 5+4.5\cdot (2\cdot 6.4+2\cdot 5)=134.6{\text{dm}}^2$

Try another example