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1   weight 6 ping pongs with another 6 ping pongs. see which side is heavier5.39.217.764 S2 R3 [+ k) n4 X& |
2   spilt the heavier side ping pongs in half and weight against each other
& ~/ S- Q) l( `6 ]3   weiht either ping pongs one on one then you will know which is the heavy one.