Question

怎样简便运算？

Answer 1

简便计算如下：
7.3x6.9+ 19.4x2.7 +12.5x5.3
=7.3x6.9+（6.9+12.5）x2.7+12.5x5.3
=7.3x6.9+6.9x2.7+12.5x2.7+12.5x5.3
=（7.3+2.7）x6.9+12.5x（2.7+5.3）
=10x6.9+12.5x8
=69+100
=169

Answer 2

=（10-2.7）×6.9+19.4×2.7+12.5×5.3

=10×6.9-2.7×6.9+19.4×2.7+12.5×5.3

=69+（19.4-6.9）×2.7+12.5×5.3

=69+12.5×2.7+12.5×5.3

=69+12.5×（2.7+5.3）

=69+100

=169

Answer 3

Answer 4

给你提供一个思路哦，就是19.4=6.9+12.5
然后运用分配律和结合律，就可以做出来了。

Answer 5

运用加法的交换律结合律进行计算，要求学生善于观察题目，同时要有凑整意识。