Arun Barun Karun can do a piece of work in more than 8 days. Arun and Karun working together can do the same work in less than 20 days. They all worked together for 7 days and then Barun worked alone for 4 more days to complete the work. If the number of days for which Barun needs to complete the work is an integer, then what is the number of possible values for the same?