Is it just me, or does there seem to be quite a few teabag question posts floating around... ?

]]>Anyway, I think Rod's got it. If you select as your sample sizes successive powers of two, then weigh the lot. Subtract the weight from what it would be if all were running smoothly (10230), convert the result to binary, and you'll be able to to tell based on which bits are set which machines are working properly or not.

]]>Now the variation here is... Not just one machine is defected. Some machines are defected. You dont know if it is 1,2,3 or all. You have to find which machines are defected. You can weigh only one time. (Assume that you have an unlimited number of sample bags from each machine)

Since you know the answer for the original riddle this one must be easy

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