69*101*394-157-43如何简便计算

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69*101*394-157-43如何简便计算
69*101*394-157-43如何简便计算

69*101*394-157-43如何简便计算
69 X 101 X 394 - 157 - 43
= 6969 X 394 - (157 + 43)
= (7000 - 31)(400 - 6) - 200
= 7000 X 400 - 7000 X 6 - 31 X 400 + 31 X 6 - 200
= 2800 000 - 42 000 - 12400 - 200 + 186
= 2758 000 - 12400 - 14
= 2758 000 - 12 414
= 2745 586

69*101*394-157-43
=69*(100+1)*(400-6)-(157+43)
=(6900+69)*(400-6)-(157+43)
=6900*400-6900*6+400*69-69*6-200
=2760000-(7000-100)*6+400(70-1)-(70-1)*6-200
=2760000-42000+600+28000-400-420+6-200
=2745586

69*101*394-157-43
=69*(100+1)*(400-6)-(157+43)
=69*100*(400-6)+69*1*(400-6)-200
=69*100*400-69*100*6+69*400-69*6-200
=2760000-41400+27600-414-200
=2745586