10,20,30,40,50,60,70,80怎么加起来都等于180

问题描述:

10,20,30,40,50,60,70,80怎么加起来都等于180

10+20+70+80=180
30+40+50+60=180一共是7个18010+30+60+80=14010+40+50+80=18020+30+60+70=18020+40+50+70=18020+30+50+80=180