[{"id":"1234","applicant":[{"phone":[{"prirotynumber":"1","areacode":"407","linenumber":"1234","exchangenumber":"7899"},{"prirotynumber":"27","areacode":"407","linenumber":"1234","exchangenumber":"79999"}]}]}]

db.collection.aggregate([{"$match":{"id":"1234","applicant.phone.prirotynumber":"1"}},{"$unwind":"$applicant"},{"$unwind":"$applicant.phone"},{"$match":{"applicant.phone.prirotynumber":"1"}},{"$set":{"homePhoneNumber ":{$concat:["$applicant.phone.areacode","-","$applicant.phone.linenumber","-","$applicant.phone.exchangenumber"]}}}])