[
  "Draw a bar model. Let total nails = 25 units. Cupboard = 4/5 x 25 = 20 units. Remainder = 5 units. Shoe-rack = 1/5 x 5 = 1 unit. Left = 4 units.",
  "4 units = 48 nails, so 1 unit = 48 / 4 = 12 nails. Cupboard = 20 x 12 = 240. Shoe-rack = 1 x 12 = 12.",
  "Difference: 240 - 12 = 228. Answer: 228."
]