The wall

We have to build a cuboid wall with dimensions based on 30 cm and 45 cm and a height of 3.25 meters. Calculate how many we need bricks if we spend 400 pieces of bricks to 1 m³ of the wall.

Correct answer:

n =  176

Step-by-step explanation:

$$\begin{gathered} a=30\text{cm}\to \text{m}=30:100\text{m}=0.3\text{m} \\ b=45\text{cm}\to \text{m}=45:100\text{m}=0.45\text{m} \\ c=3.25\text{m} \\ V=a\cdot b\cdot c=0.3\cdot 0.45\cdot 3.25=\frac{351}{800}\doteq 0.4388{\text{m}}^3 \\ n=V\cdot 400=0.4388\cdot 400=176 \end{gathered}$$

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