6 3/4 * 1 1/3-(1 5/12+7/8)/ 1 5=?

1)15/12+7/8=30/24+21/24=51/24
2)51/24/15=51/360
3)63/4*11/3=693/12
4)693/12-51/360=20790/360-51/360=20739/360=6913/120