An online furniture store sells chairs for $100 each and tables for $550 each. Every day, the store can ship at most 25 pieces of furniture and must sell no less than $7000 worth of chairs and tables. If 9 chairs were sold, determine all possible values for the number of tables that the store must sell in order to meet the requirements. Your answer should be a comma separated list of values. If there are no possible solutions, submit an empty answer.