select sum column by with MongoDB and Laravel?

I have MongoDB document which contains following data(xxx)

{ 
   "_id" : "48e5f6b1-026f-48b8-98cb-6572cfa0eaa6", 
   "esti_delivery_time" : "2015-1-1",
   "original_price" : NumberInt(4060),
   "price":109.2,
   "code" : "JS1709137", 
   "updated_at" : ISODate("2017-09-13T06:01:18.000+0000"), 
   "created_at" : ISODate("2017-09-13T03:45:54.000+0000")
}

I want to

SELECT "xxx" with SUM "price" and SUM "original_price"]
Thank you so much.