9.85×999+98.5×1,简便计算

问题描述:

9.85×999+98.5×1,简便计算

9.85×999+98.5×1
=9.85x(999+1+9)
=9.85x1000+9.85x9
=9.85x1000+9.85x(10-1)
=9850 +98.5-9.85