SOLUTION: Can I please get help with thus problem. A box contains 3 defective bulbs and 9 good bulbs.if 5 bulbs a chosen without replacement what is the expected number of defective bulbs?

Question 430482: Can I please get help with thus problem.
A box contains 3 defective bulbs and 9 good bulbs.if 5 bulbs a chosen without replacement what is the expected number of defective bulbs? I got 3.74.
Thanks
Gina
Answer by ewatrrr(24785) (Show Source): You can put this solution on YOUR website!

 

Hi

A box contains 3 defective bulbs and 9 good bulbs. 3/12 OR 1/4 DEFECTIVE

expected number of defective if 5 were chosen = .25*5 = 1.25 

would expect 1.  

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