(1+0.23+0.34)×(0.23+0.34+0.56)-(1+0.23+0.34+0.56)×(0.23+0.34
1个回答

解题思路:通过观察,此题中的数据很有特点,于是根据题中数据,设1+0.23+034=a,0.23+0.34=b,那么a-b=1+00.23+0.34-(0.23+0.34)=1.于是原式变为a×(b+0.56)-(a+0.56)×b=0.56×(a-b),把a-b=1,代入即可求出.

设1+0.23+034=a,0.23+0.34=b,那么a-b=1+00.23+0.34-(0.23+0.34)=1.

(1+0.23+0.34)×(0.23+0.34+0.56)-(1+0.23+0.34+0.56)×(0.23+0.34),

=a×(b+0.56)-(a+0.56)×b,

=ab+0.56a-ab-0.56b,

=0.56a-0.56b,

=0.56×(a-b),

=0.56×1,

=0.56.

点评:

本题考点: 四则混合运算中的巧算.

考点点评: 解决这类问题,应注意审题,根据数字特点,运用运算技巧,巧妙解答.