[{"_id":ObjectId("5ef1cd704b35c6d6698f2050"),"Name":"TD","Date":ISODate("2021-06-23T09:37:51.976Z"),"A":"20.4","B":2.04},{"_id":1,"Name":"TD1","Date":ISODate("2021-06-24T09:37:51.976Z"),"A":"10.4","B":1.004},{"_id":2,"Name":"TD2","Date":ISODate("2021-06-22T09:37:51.976Z"),"A":"10.4","B":2.04}]

db.collection.aggregate([{"$match":{"Date":{"$gte":ISODate("2020-01-01")}}},{"$set":{"ratio":{"$divide":["$B",{"$toDouble":"$A"}]}}},{"$match":{"ratio":{"$lte":0.1}}},{"$sort":{"ratio":1}},{"$project":{"ratio":0}}])