0,2^3*15 = 0,12 cm^3
Spigolo S = ³√(500-0,12)/4 = ³√125 = 5,0 cm
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Volume di ciascun cubo grande:
$V= \dfrac{1}{4}\left(500,12-15×0,2^3\right)$
$V= \dfrac{1}{4}\left(500,12-15×0,008\right)$
$V= \dfrac{1}{4}\left(500,12-0,12\right)$
$V= \dfrac{1}{\cancel4_1}×\cancel{500}^{125}$
$V= 125\,cm^3;$
per cui:
spigolo del cubo grande $s= \sqrt[3]{125} = 5\,cm.$