Amount of work K can do in 1 day = 1/16
Amount of work L can do in 1 day = 1/12
Amount of work K, L and M can together do in 1 day = 1/4
Amount of work M can do in 1 day = 1/4 - (1/16 + 1/12) = 3/16 – 1/12 = 5/48
=> Hence M can do the job on 48/5 days = 9 (3/5) days