[
  "Draw a bar model. Let the total nails be 24 units (LCM of denominators 6 and 4).",
  "Cupboard uses 5/6 = 20 units, leaving 4 units. Shoe-rack takes 1/4 of 4 = 1 unit. Nails left = 3 units = 36, so 1 unit = 12 nails.",
  "Total nails = 24 units x 12 = 288. Answer: 288 nails."
]