divde the 12 balls into 3 sets of 4.
) |1 ]" s- u- s1 E) oweight any 2 sets.公仔箱論壇# F! u9 B% A, V9 h; H3 a, z- e
if the 2 sets are equal, then you know the heavy one is in the third
5 @" G5 B% M( Y$ l' v+ ~if one of the 2 is heavier, then the heavy one is in that set
) P$ A/ k) D8 O7 M; vtvb now,tvbnow,bttvbthen divide the 4 balls into 2.
% L6 D1 K! K7 ]weigh them
9 j9 t6 {( V! v公仔箱論壇and divide the heavier into 1
" d; l/ y1 E/ h# Btvb now,tvbnow,bttvband weight them.
& Z, J9 T: `0 V Z' m3 G3 R4 D% [公仔箱論壇3 x weighing and get the ans. 5.39.217.77:8898% Q' t2 {! m5 | @2 M, P5 c
in less than 15 secs. |