["Find the volume of the cube: 30 x 30 x 30 = 27,000 cm^3.",
"Find the volume poured into the tank: 15 x 10 x 10 = 1,500 cm^3.",
"Fraction left = (27,000 - 1,500) / 27,000 = 25,500 / 27,000. Simplify to 17/18."]