12.5*15+12.5*57简便计算_数学解答

12.5*15+12.5*57简便计算

人气：219 ℃　时间：2020-04-15 21:21:18

解答

12.5*15+12.5*57
=12.5*(15+57)
=12.5*72
=12.5*(80-8)
=12.5 *80-12.5*8
=1000-100
=900