Metal sheet

The box has the shape of a cube with an edge length of 50 cm. How much m² of sheet metal is needed to beat a box if we add 20% on the folds of the lid and walls?

Correct answer:

x =  1.8 m²

Step-by-step explanation:

$$\begin{gathered} q=100\%+20\%=1+\frac{20}{100}=1.2 \\ a=50\text{cm}\to \text{m}=50:100\text{m}=0.5\text{m} \\ S=6\cdot a^2=6\cdot 0.5^2=\frac{3}{2}=1.5{\text{m}}^2 \\ x=q\cdot S=1.2\cdot 1.5=1.8{\text{m}}^2 \end{gathered}$$

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