Fence elements

Mr. Winter is building a fence from perforated brick elements in the shape of a cuboid with dimensions of 15 cm, 15 cm, and 20 cm. the fence will be 15 cm wide, 150 cm high, and 10 m long. The mortar space will occupy 0.25 m³. How many brick elements does it probably use?

Final Answer:

n =  444

Step-by-step explanation:

$$\begin{gathered} a=15\text{cm} \\ b=15\text{cm} \\ c=20\text{cm} \\ A=15\text{cm} \\ B=150\text{cm} \\ C=10\cdot 100=1000\text{cm} \\ {V}_1=0.25\cdot 100^3=250000{\text{cm}}^3 \\ {V}_2=a\cdot b\cdot c=15\cdot 15\cdot 20=4500{\text{cm}}^3 \\ {V}_3=A\cdot B\cdot C-V_1=15\cdot 150\cdot 1000-250000=2000000{\text{cm}}^3 \\ n=V_3/V_2=2000000/4500=444 \end{gathered}$$

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