put 3 balls on each side, www1.tvboxnow.com; x( x9 ]+ z6 w! Q. R4 s# B
if balance, we can prove that all 6 balls on the 天平 is normal, & F5 J& C3 }, t' V3 f" p: n
if not balance, we can prove that the 6 balls outside the 天平 is normal.www1.tvboxnow.com* @4 p1 ?* X% r
then use the proved-normal ball on one side and put the other ball on other side 公仔箱論壇8 y( g# B4 G& s; B* M4 Q
to determine the abnormal is heavy and light |