0.81乘0.81乘99 怎么用简便方法计算?

分类: 作业答案 • 2021-12-24 16:18:59

问题描述：

答

0.81乘0.81乘99
=0.81X0.81X99
=0.81X0.81X(100-1)
=0.81X0.81X100-0.81X0.81
=0.81X81-0.81X0.81
=0.81X(81.0.81)
=0.81X80.19
=64.9539