SOLUTION: a shipment of 9 printers contains 4 that are defective. find the probability that a sample size of 2, drawn from the 9, will not contain a defective printer ? Please answer fas

Algebra ->  Probability-and-statistics -> SOLUTION: a shipment of 9 printers contains 4 that are defective. find the probability that a sample size of 2, drawn from the 9, will not contain a defective printer ? Please answer fas      Log On


   

Question 825062: a shipment of 9 printers contains 4 that are defective. find the probability that a sample size of 2, drawn from the 9, will not contain a defective printer ?
Please answer fast !
Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
The probability that any one of the 9 printers will not be defective is 5%2F9 .
If you pick one that is not defective, you will have 8 printers to choose a second printer from,
and 4 of those are defective, so your chance of picking a second good one is
4%2F8=1%2F2 .
Multiplying, you find that you would pick 2 good printers
%285%2F9%29%281%2F2%29=5%2F18 of the time.
Your probability of picking 2 good printers from that lot is
highlight%285%2F18%29=0.278 (rounded) or 27.8%.