86乘8584减84乘8586
问题描述：
86乘8584减84乘8586
一定要简便计算
答
86*8584-84*8586
=(84+2)*8584-84*(8584+2)
=84*8584+2*8584-84*8584-84*2
=2*(8500+84)-2*84
=2*8500
=17000