{
  "prompt": {
    "id": "maths-04",
    "category": "maths",
    "kind": "puzzle",
    "title": "Birthday surprise",
    "text": "How many people do you need in a room for a better than even chance that two share a birthday? Explain why the answer feels wrong.",
    "tags": [
      "probability"
    ]
  },
  "recent_replies": []
}