[{"_id":1,"price":[{"PRICE_A":3098.67},{"PRICE_B":3166.67},{"PRICE_C":3800}]},{"_id":2,"price":[{"PRICE_A":679.6},{"PRICE_B":781.6},{"PRICE_C":938}]}]

db.collection.aggregate([{"$match":{"price.PRICE_A":{"$gte":50,"$lte":5000}}},{"$sort":{"price.PRICE_A":1}}])