7/6-5/8-3/8=7/6-(5/8+3/8)=7/6-1=1/6
7/6—5/8 +3/8简便计算=7/6-2/8=7/6-1/4=(14-3)/12=11/12
7/6-5/8-3/8=7/6-(5/8+3/8)=7/6-1=1/67/6—5/8 +3/8=7/6-2/8=7/6-1/4=14/12-3/12=11/12