0.3×9.9+0.2简便算法
问题描述:
0.3×9.9+0.2简便算法
答
0.3×9.9+0.2
=0.3×(10-0.1)+0.2
=0.3×10-0.3×0.1+0.2
=3-0.03+0.2
=3.17