[
  "Find how many 5-cm cubes fit along each edge of the box.",
  "40 &divide; 5 = 8 (length), 25 &divide; 5 = 5 (width), 20 &divide; 5 = 4 (height).",
  "Multiply: 8 &times; 5 &times; 4 = 160."
]