divde the 12 balls into 3 sets of 4.
9 f% C3 ?6 S0 b. kwww2.tvboxnow.comweight any 2 sets.! S9 a+ I' y N0 `" D
if the 2 sets are equal, then you know the heavy one is in the third
# b. ~3 y; W7 H+ g7 |$ L. h: [$ {' lif one of the 2 is heavier, then the heavy one is in that settvb now,tvbnow,bttvb: S7 B$ ~+ q/ B h- q% z
then divide the 4 balls into 2.
. |7 S8 ?- n: u) m' w8 ltvb now,tvbnow,bttvbweigh themwww2.tvboxnow.com1 c3 ?5 I9 Q/ C: a/ z* D
and divide the heavier into 1www2.tvboxnow.com5 ^7 P2 U$ v1 k* V) Q9 ]2 x7 i# P1 V
and weight them.2 i/ u0 \. X& X- d
3 x weighing and get the ans.
- i/ o |( E& M& Zin less than 15 secs. |