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(1+0.23+0.45)*(0.45+0.67+0.89)-(1+0.45+0.67+0.89)*(0.23*0.45)

题目详情
(1+0.23+0.45)*(0.45+0.67+0.89)-(1+0.45+0.67+0.89)*(0.23*0.45)
▼优质解答
答案和解析
设0.23+0.45=a,0.45+0.67+0.89=b
原式=(1+a)b-(1+b)a
=b+ab-a-ab
=b-a
=(0.45+0.67+0.89)-(0.23+0.45)
=0.67+0.89-0.23
=1.33