Well..divided into 6/6 first to define a heavier group is certainly right. Randomly select 3/3 will result another heavier group.
' i7 n! g$ _$ f; `! Q" `+ t* aThe problem is we don't know the weight of each individual ball, so it will not be accurate to figure out which ball is irregular by only weight them once.$ C3 G- S# t T2 S
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