These achievements can easily be boosted online if you don't have the l33t skillz needed to get them legit. Get a friend to do it with you or find someone in our Achievement Trading Thread (clickable) to help you out. Now, create a ranked match from the Xbox Live Battle menu. Set round count to 1, time limit to 30 seconds and language preferences to "other". Now, have your friend search with the same preferences and you shouldn't have any trouble finding each other. In case some lost soul wanders into your lobby, just quit out and keep retrying until your boosting buddy joins.
NOTE: Championship matches do not count towards the Ranked achievements!