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Probability of bulb testing

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Probability of bulb testing

by pakaskwa » Fri Mar 06, 2009 1:46 am
If you test 2 different lightbulbs from a box of 100 lightbulbs that contain 1 defective lightbulb, what is the probability that both lightbulbs that you test are defective?
A. 0
B. 0.0001
C. 1/9900
D. 0.01
E. 1/99

OA answer is A. Can you please explain?
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by kamu » Fri Mar 06, 2009 1:57 am
:shock:

The question says there is only one defective bulb.,

We cannot possibly find two different defective bulbs!

A is the only possible answer!!!
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by pakaskwa » Fri Mar 06, 2009 2:12 am
My understanding of the question was that they only tested the first 2 bulbs.

Do you think it's a fair question?
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