put 3 balls on each side,
5 n Q2 N# L2 U' g2 J4 Jif balance, we can prove that all 6 balls on the 天平 is normal, 5.39.217.77: w& E# a; w/ `* l5 [- {6 n5 _9 t2 Y' v
if not balance, we can prove that the 6 balls outside the 天平 is normal.
, s/ C3 P! X( \3 C2 f; m3 n5.39.217.77then use the proved-normal ball on one side and put the other ball on other side % C- a. K' w$ B
to determine the abnormal is heavy and light |