Divide the 12 balls into 4 groups of 3's.! ]: T8 s8 M3 m% F
Weigh group 1 & 2 9 o$ u: y$ S* v2 _* ~5 c2 x5.39.217.77then weigh group 2 & 3 2 r3 M Z7 i5 }4 FIf the results are Equal & Equal, it means the ball with the different weight is in group 4. 3 Q3 c" K4 B* iIf the results are Equal & Unequal, it means the ball is in group 3.5.39.217.77' J+ }+ M7 H% d2 [9 z
If the results are Unequal & Equal, it means the ball is in group 1. 0 u' [# n- w% W2 l/ QIf the results are Unequal & Unequal, it means the ball is in group 2. 4 r1 N9 R$ E( n5.39.217.77 & X" C1 X! g2 _9 D: N) JOnce you determine the group that contains the ball.; U8 k0 a% B1 ^+ Z
Simply weigh two of the balls