398×2556×199+56怎么简算
问题描述：
398×2556×199+56怎么简算
答
398×2556×199+56=400X2556×199-2X2556X199+56=400X2556X200-400X2556-400X2556+2X2556+56=80000X2556-800X2556+2X2556+56=79202X2556+56=39601X5000+79202X56+56=198005000+79203X56=198005000+79203X60-79203X4=...