728*359-628*359+641*1000
728*359-628*359+641*1000=359*(728-628)+641*1000=359*100+641000=35900+641000=676900
1) 728*359=261352
2) 628*359=225452
3) 641*1000=641000
4) 261352-225452=35900
5) 35900+641000=676900