简便计算:19又15/16*(-8)(-99)*999

问题描述:

简便计算:19又15/16*(-8)
(-99)*999

19又15/16*(-8)
=(20-1/16)*(-8)
=-160+1/2
=-159又1/2
(-99)*999
=-99×(1000-1)
=-99000+99
=-98901

19又15/16*(-8)
=(20-1/16)×(-8)
=20×(-8)-1/16×(-8)
=-160+1/2
=-159又1/2
(-99)*999
=(-99)×(1000-1)
=-99×1000-1×(-99)
=-99000+99
=-98901