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1   weight 6 ping pongs with another 6 ping pongs. see which side is heavierTVBNOW 含有熱門話題，最新最快電視，軟體，遊戲，電影，動漫及日常生活及興趣交流等資訊。, e5 w# P6 \; w7 b$ c( }
2   spilt the heavier side ping pongs in half and weight against each other
/ q% g6 y  h" m, s3   weiht either ping pongs one on one then you will know which is the heavy one.