15.37*7.88-9.37*7.88-15.37*2.12+9.37*2.12= *=乘号要简便计算快
问题描述：
15.37*7.88-9.37*7.88-15.37*2.12+9.37*2.12= *=乘号
要简便计算
快
答
2006÷（2006＋2006÷2007）
答
15.37*7.88-9.37*7.88-15.37*2.12+9.37*2.12
=7.88*(15.37-9.37)-2.12*(15.37-9.37)
=7.88*6-2.12*6
=6*(7.88-2.12)
=6*5.7
=34.2
答
15.37*(7.88-2.12)-9.37*(7.88-2.12)
=(7.88-2.12)*(15.37-9.37)
=5.76*(15.37-9.37)
=5.76*6
=34.56