Question

21×77-27×34+13×77,简便运算？

Answer 1

如图，根据式子的结合律，分配律运算

Answer 2

21×77-27×34+13×77简便运算如下：
21×77-27×34+13×77
=21×77+13×77-27×34
=（21+13）×77-27×34
=34×77-27×34
=34×（77-27）
=34×50
=1700

Answer 3

简便计算是把其中两项直接提取公约数77得
77x(21+13)-27x34
=77x34-27x34
=34x(77-27)
=34x50
=1700

Answer 4

21*77-27*34+13*77
=77(21+13)-27*34
=77*34-27*34
=34(77-27)
=34*50
=1700

Answer 5

如图所示，根据公式的组合规律和分布规律