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44 votes
Twenty of the 50 digital video recorders (DVRS) in an inventory are known to be detective What is the probability that a randomly selected item is defective?​

User Keyneom
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1 Answer

17 votes
17 votes

Answer:

3/5

Explanation:

Remember that odds for plus odds against must be 1. Therefore, 20 out of 50 of the DVRs are defective, so 30 out of 50 would work.

30/50

simplifies into 3/5 so that would be the probability of you picking out a DVR that works, and the probability of picking one that does not work would be the leftover 2/5 . Or, if you're answering with a percent, you would have a 60% chance of picking a working DVR.

I hope this helps, I know the explanation isn't really clear, but I can't really think of another way to explain it.

User Artur Sapek
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