0.85x199=0.85*(200-1)=0.85*200-0.85=170-0.85=169.15

原式=0.85x199+(0.25x4)x8.5=0.85x199+1x8.5=0.85x199+8.5=0.85x200-0.85+8.5=170-0.85+8.5=169.15+8.5=177.65

0.85x198=0.85x(198+2)-0.85x2=0.85x200-1.7=170-1.7=168.3

354*199=354*(200-1)=354*200-354*1=70800-354=70446 你好,本题已解答,如果满意 请点右上角“采纳答案”.

=0.85*(1-0.01)=0.85*1-0.85*0.01=0.85-0.0085=0.8415

简便方法计算0.85乘99=0.85x(100-1)=0.85x100-0.85=85-0.85=84.15

0.85x199 =0.85*(200-1)=0.85*200-0.85*1=170-0.85=169.150.25x36=0.25*(4*9)=(0.25*4)*9=1*9=975x99+2x75=75*(99+2)=75*101=75*100+75*1=7500+75=7575

3.25X199 =3.25X(200-1) =650-3.25 =646.75

3.25x199=3.25x(200-1)=3.25x200-3.25=650-3.25=646.75 求采纳