小学数学五年级上册小数乘法简算口算练习.ppt

文档介绍：×199 125×
= ×(200—1) =125××11
=×200—×1 =×199 125×
= ×(200—1) =125××11
=×200—×1 =100×11
=940- =1100
=
25××125 (20+1)×
=〔25×〕×〔8×125〕 =20×+
=10×1000 =+
=10000 =
104× ×125
=(100+4) × =9×(×125)
=100×+4× =900
=25+1
=26
××4 -(+)
=7-
=
× ×-
= ×(10+) = ×(-)
=×10+× =58
=88+
=
×-× -
=×(-) =- 4+
=× =
=1
672-- 848-269-131-48
=672-(+) =848-48-269-131
=672-10 =800-(269+131)
=662 =800-400
=400
×63+6