3.14×0.8+3.14×0.2 回答者: swyebubi | 五级 | 2008-9-14 17:33 456+198=456+200-2=654 99×98=(100-1

问题描述:

3.14×0.8+3.14×0.2 回答者: swyebubi | 五级 | 2008-9-14 17:33 456+198=456+200-2=654 99×98=(100-1

3.14×0.8+3.14×0.299×98
=3.14×(0.2+0.8) =(100-1)×98
=3.14×1=100×98-1×98
=3.14=9800-98
=9702