SOLUTION: There are four batteries, and one is defective. Two are to be selected at random for use on a particular day. Find the probability that the second battery selected is not defective

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Question 1179596: There are four batteries, and one is defective. Two are to be selected at random for use on a particular day. Find the probability that the second battery selected is not defective, given that the first was not defective.
Answer by ikleyn(52803) About Me  (Show Source):
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There are four batteries, and one is defective. Two are to be selected at random
for use on a particular day. Find the probability that the second battery selected is not defective,
given that the first was not defective.
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Originally, we have 4 batteries, of which one is defective and three are good.


Given that the first selected battery is good, leaves us 3 batteries to chose from, 

of which one is defective and two others are good.


The probability to select the 2nd battery good is  P = 2%2F3.     ANSWER

Solved, answered and explained.


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