99*87.5+87.5=(99+1)*87.5=875
75*4.67+17.9*2.5=2.5*30*4.67+17.9*2.5=2.5*(30*4.67+17.9)=2.5*(140.1+17.9)=2.5*158=395
808*0.125=(800+8)*0.125=800*0.125+8*0.125=101
99乘87.5加87.5简便运算 75乘4.67加17.9乘2.5 简便运算 808乘0.125简便运算
99*87.5+87.5=(99+1)*87.5=875
75*4.67+17.9*2.5=2.5*30*4.67+17.9*2.5=2.5*(30*4.67+17.9)=2.5*(140.1+17.9)=2.5*158=395
808*0.125=(800+8)*0.125=800*0.125+8*0.125=101