文档介绍：:800-400=         1400-200=        300+600=         800-50=        400+300=1000-400=       300+500=         900-650=         500+900=        900-700=300-200=        200+500=       400+300=         1400-300=       400+300=500+300=       300+1200=         900-100=         400+300=      200-100= 200+3100=      1300-100=        1700+200=        500-100=       300+400=1000-300=       200+300=         200-100=          300+500=       800-200=200+300=         700-250=        300-100=          400+500=       400-100= :800-400=         1400-200=        300+600=         800-50=        400+300=1000-400=       300+500=         900-650=         500+900=        900-700=300-200=        200+500=       400+300=         1400-300=       400+300=500+300=       300+1200=         900-100=         400+300=      200-100= 200+3100=      1300-100=        1700+200=        500-100=       300+400=1000-300=       200+300=         200-100=          300+500=       800-200=200+300=         700-250=        300-100=          400+500=       400-100=2、用竖式计算889-466=         445-277=         356+626=         865-508=        445+385=  986-455=       345+543=         957-679=          531+975=       989-799= 382-274=        258+553=       445+369=         468-389=        457+368=  2