-5-5/24-2-5/9-10-11/18+12+5/6
=-5-2-10+12-5/24-5/9-11/18+5/6
=-5-15/72-40/72-44/72+60/72
=-5-99/72+60/72
=-5-39/72
=-5-13/24
=-5又13/24