(1+0.12+0.23)×(0.12+0.23+0.34)-(1+0.12+0.23+0.34)×(0.12+0.23)=_.

(1+0.12+0.23)×(0.12+0.23+0.34)-(1+0.12+0.23+0.34)×(0.12+0.23)=_.

题目
(1+0.12+0.23)×(0.12+0.23+0.34)-(1+0.12+0.23+0.34)×(0.12+0.23)=______.
答案
设0.12+0.23=x,0.12+0.23+0.34=y.
则:(1+0.12+0.23)×(0.12+0.23+0.34)-(1+0.12+0.23+0.34)×(0.12+0.23)
=(1+x)y-(1+y)x,
=y+xy-x-xy,
=y-x,
=(0.12+0.23+0.34)-(0.12+0.23),
=0.12-0.12+0.23-0.23+0.34,
=0.34.
故答案为:0.34.
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