Loss of accuracy in parsing floats

When parsing the next JSON line, the float value for the x coordinate changes.

{
 "spatialReference": {
   "wkid": 4326
 },
 "candidates": [
   {
     "address": "240000001",
     "location": {
       "x": -79.939219121531494,
       "y": 40.852153506889806
     },
     "score": 100,
     "attributes": {

     }
   }
 ]}

When calling JObject.Parse in the previous xml, it is converted to

 {
  "spatialReference": {
    "wkid": 4326
  },
  "candidates": [
    {
      "address": "240000001",
      "location": {
        "x": -79.9392191215315,
        "y": 40.852153506889806
      },
      "score": 100,
      "attributes": {}
    }
  ]
} 
                         

x/y ?