1 weight 6 ping pongs with another 6 ping pongs. see which side is heavier
$ |* |( M, X, u$ W) z- Q2 spilt the heavier side ping pongs in half and weight against each other
& B: R, p0 A9 N. L5 W; Z公仔箱論壇3 weiht either ping pongs one on one then you will know which is the heavy one. |