文档介绍:-
. 优选-
用简便方法计算
25××4                     5××
36×15×2                      36××   
45×102                              45×  
34×27+34×73                        34×+34×  
86×99+86                             ×99+   
125×88                               × 
++ ++ +(-)
++ -- -(+)
-
. 优选-
+- +-+ ---
+++ +- --
+-+ -+ ---
-+ ++ +-+
-- ××4 (-)×8
×102 ×+× --
×--× ×+78× 32+-
× ×+ ×-×
-
. 优选-
-(-) ÷ 320÷÷8
×+ ÷÷ -+-
÷ ÷÷ ×99+
÷(×4) ÷ ××32 ×
÷÷4 × -(23+)
×+× ××8 ×99+
×-× ÷÷ ×101 ××
(-)÷8÷ ×+× ÷÷÷÷
-
.