{
  "question_id": 5116,
  "hints": [
    {
      "hint_level": 1,
      "hint": "Book costs 6 times the pen."
    },
    {
      "hint_level": 2,
      "hint": "Total = pen + 6 x pen = 7 x pen."
    },
    {
      "hint_level": 3,
      "hint": "Pen = total / 7 = x / 7."
    }
  ]
}