1. 1st divide to half take the heavier out0 Z5 \# r: m3 O& K
2. 2nd take 4 balls out of 5 divide 2 groups to get the heavier out. (if is equal thn the remain is the one u looking for) " x5 ]$ h9 y4 n2 S% m' Y( U公仔箱論壇3. Same method if is not equal on 2nd try.