divde the 12 balls into 3 sets of 4. - r, ~: _ G4 @% O5 S4 c Q, q9 A
weight any 2 sets.
9 E' G! v+ c8 p$ O7 i9 X9 nTVBNOW 含有熱門話題,最新最快電視,軟體,遊戲,電影,動漫及日常生活及興趣交流等資訊。if the 2 sets are equal, then you know the heavy one is in the third+ n ~' t6 v2 O' Q! R
if one of the 2 is heavier, then the heavy one is in that set
' E) U/ r3 ^" K- J" }# V7 l1 e0 jthen divide the 4 balls into 2.
* F+ T. W) B' P$ @/ r! b1 w, Z公仔箱論壇weigh them
* z6 S- r/ E' [# s5 @- Z$ Dand divide the heavier into 15.39.217.776 ?9 e: U& ]9 V4 m; z& y. Z
and weight them.5.39.217.779 O; A6 w3 i; F2 V0 b. Z; M# }3 D3 K
3 x weighing and get the ans. & G& C/ f/ E* W9 v, h2 o
in less than 15 secs. |