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Suppose you just received a shipment of twelve televisions. Three of them are defective. Assuming that two televisions are randomly selected, find the following probabilities:

What is the probability that both televisons work?
What is the probability that at least one does not work?

2 Answers

5 votes

Answer:

Explanation:

User Ahmed Kamal
by
8.2k points
6 votes
The probability that both televisons work is 18/33.
The probability that at least one does not work is 15/33.

Let x = number of shipments, x = 12
P(defective) = 3/12
P(working) = 9/12
The probability that two randomly selected televisions are both working is:
9/12 * 8/11 = 72 / 132 or 18/33
P(2 working) = 18/33
8/11 is used for the second selection since the number of televisions has been reduced due to the first selection.

The probability of 1 not working among the two can be solved through"
P(at least one defective among the 2) = 1 - P(2 working)
P(at least one defective among the 2) = 15/ 33

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User Paul Farnell
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