among 18 computers, 12 are in working order and six are defective. How many sample of 4 are possible, selected without replacement and without regard to order, wherein all are defective?

Guest Aug 7, 2017

2+0 Answers




Since we know beforehand that we're only choosing amongst the defective ones, we want to choose any four of the six defectives  = C(6,4)  = 15 possible different samples of defectives



cool cool cool

CPhill  Aug 7, 2017

 We have 10 computers. 5 are taken, meaning being used, while the others are open. How many are open? If we bought 100 more computers, and the 5 that are being used were still used, how many computers would be open? 

Guest Aug 7, 2017
edited by Guest  Aug 7, 2017

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