脱式计算(3/4+1/6)*2/3 =3/4*2/3+1/6*2/3=1/2+1/9=11/1825*1/5-5*1/5 =5-1=46/11*7/15*10 =84/33=28/11(1/7+1/4)*28=1/7*28+1/4*28=4+7=11 (21+2/5)*5/7 =21*5/7+2/5*5/7=15+2/7=15又2/739*7/13*2/3=14