15/16+（8/9-2/3）*1/2 =15/16+4/9-1/3=15/16+1/9=151/144720/12/5=720/(12*5)=720/60=12题目应是4.89*6.3+48.9*0.37= 4.89*6.3+4.89*3.7= 4.89*(6.3+3.7)= 4.89*10=48.97.6*1.01=7.6*(1+0.01)=7.6+0.076=7.676...