[1又1/3减(0.2+1/3)*4.5]+13又1/2=[1又1/3减8/15*4.5]+13又1/2=4/3-2.4+13.5=4/3+11.1=12又13/3012又3/4-2又2/5*3又3/4/2又1/2=12又3/4-12/5*15/4/2.5=12又3/4-9/2.5=12.75-3.6=9.156.3/（2.6+5又1/3*1又7/8）=6.3/...