The volume of water that the restaurant saves is; 12.87 cm³
Volume of a cube = x³
where x is side length
Thus;
Volume of Ice cube with a side length of 3 cm is;
V_ice cube = 3³ = 27 cm³
Side length is now halved and so;
New side length = 3/2 = 1.5 cm
Thus;
New Sphere volume = ⁴/₃πr³
New Sphere volume = ⁴/₃π * 1.5³
New Sphere volume = 14.13 cm³
Thus;
Amount of water saved = 27 - 14.13 = 12.87 cm³
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