A lady builds 10cm length, 18cm width, and 4cm height box using 12cubic cm cubes. What is the minimum number of cubes required to build the box?
Answers: A) 107 B) 70 C) 78 D) 60 E) 111

Rationale: "number of cubes required = volume of box / volume of cube = 10 * 18 * 4 / 12 = 60 cubes answer : d"
Answer: D