Cardboard box

We want to make a cardboard box shaped quadrangular prism with rhombic base. Rhombus has a side of 5 cm and 8 cm one diagonal long. The height of the box to be 12 cm. The box will be open at the top. How many square centimeters cardboard we need, if we calculate to the overlap and joints need 5% of the cardboard?

Result

S =  277.2 cm2

Solution:

$S=1.05 \cdot \ (5 \cdot \ 12 \cdot \ 4 + 2 \cdot \ \sqrt{ 9 \cdot \ (9-5) \cdot \ (9-5) \cdot \ (9-8) } ) = \frac{ 1386 }{ 5 } = 277.2 \ cm^2$

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