$match two date fields and allow only if one is greater then other by 10 min [duplicate]

This question already has an answer here:

• mongodb: query for the time period between two date fields 1 answer

I am trying to find a solution on this

Json ---
{
    "job": null,

    "startedAt": ISODate("2017-01-14T14:17:48.889Z"),
    "completion": 100,
    "codeTestSubmissionId": "587a3831ce022b36580d63d7",
    "deadlineAt": ISODate("2017-01-14T14:38:03.197Z")
}

I want to match two field deadlineAt and startedAt and then find the aggrigate for the fields

what I tried is this

{$project: {
                  // All your other fields here
                  cmp_value: {$subtract: ['$deadlineAt', '$startedAt)' ] }
              }},
              { $match: { cmp_value: { $gte: 10*60*1000  } } },
              { $group: { _id: ticket.rating ? '$rating' : '$result', count: { $sum: 1 } } }

But getting error cant compare date with string Can anyone please help me on this. how can I compare and check if there is 10 min difference and then pass it to calculate aggregate?

Thanks in advance

via Rohit G