12*222.2-666.6+0.25*0.25*80简便计算

12*222.2-666.6+0.25*0.25*80简便计算
12*222.2-666.6+0.25*0.25*80
简便计算

12*222.2-666.6+0.25*0.25*80简便计算
12*222.2-666.6+0.25*0.25*80
=12*222.2-222.2*3+0.25*0.25*80
=222.2*(12-3)+0.25*(80+1)
=222.2*9+0.25*81
=222.2*9+0.25*9*9
=(222.2+2.25)*9
=224.45*9
=224.45*(10-1)
=2244.5-224.45
=2020.05

12*222.2-666.6+0.25*0.25*80 = 2 004.8