0.85x102等于0.85X(100+2)=0.85x100+0.85x2=85+1.7=86.7
85×102=85×(100+2)=85×100+85×2=8500+170=8670
85x102=85×(100+2)=85×100+85×2=8500+170=8670
80X100十5X100十2X85