2000×199.9-1997×199.8的简便计算
问题描述：
2000×199.9-1997×199.8的简便计算
答
2000×199.9-1997×199.8
=2000×199.9-2000×199.8+3x199.8
=2000x(199.9-199.8)+3x(200-0.2)
=2000x0.1+3x200-3x0.2
=200+600-0.6
=799.4