divde the 12 balls into 3 sets of 4.
" [9 u$ r5 g9 ?% H9 U, l! K; iwww1.tvboxnow.comweight any 2 sets.公仔箱論壇! l: j( w6 a: ~+ y
if the 2 sets are equal, then you know the heavy one is in the third
4 X; P1 t0 c! a/ J9 i! m( {if one of the 2 is heavier, then the heavy one is in that settvb now,tvbnow,bttvb9 D; [' F" E6 @
then divide the 4 balls into 2.
. Q3 N( Q4 r2 F" I: `% H9 gweigh them
! b1 y+ x/ J+ B! K3 `and divide the heavier into 1
& a3 M. }3 L1 ~0 Vand weight them.
# Z3 r0 c% Z$ ]4 V% ]: Z% ^3 x weighing and get the ans. : C+ k# X! Q- `* ^) j& j9 U' k
in less than 15 secs. |