199.9×19.98-19.98×1.987 简算
199.9*19.98-199.8*19.97
简算:19.99乘19.98-19.97乘19.96
199.9×19.98-19.99×199.8用简便方法怎么计算
第一讲全部答案,2000×199.9-1999×199.8 19.98×37-199.8×1.9+1.998×820 9
199.9*19.98-199.8*19.97用简便方法计算(要过程).
简算19.98×37-199.8×1.9+1998×0.82 7×13×(
计算 199.8+19.98+1.998+2.222
计算:1998+199.8+19.98+1.998.
19.98×37-199.8×1.9 1998×0.
19.99×19.98-19.97×19.96简便运算
简便计算;19.99*19.98-19.97*19.96
199.8+19.98+1.998+2.222的简便方法?