1. 1st divide to half take the heavier out公仔箱論壇! M( c" C. R0 C r$ b) _5 B
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)
3 W. v& E: L5 N, a, i, M7 r3. Same method if is not equal on 2nd try. |