SOLUTION: A recent study of the life span of portable CD players found the average to be 3.7 years with a standard deviation of 0.6 years. If a random sample of 32 people who own CD players
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Question 403303: A recent study of the life span of portable CD players found the average to be 3.7 years with a standard deviation of 0.6 years. If a random sample of 32 people who own CD players is selected, find the probability that the mean lifetime of the sample will be less than 3.4 years.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
A recent study of the life span of portable CD players found the average to be 3.7 years with a standard deviation of 0.6 years. If a random sample of 32 people who own CD players is selected, find the probability that the mean life time of the sample will be less than 3.4 years.
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t(3.4) = (3.4-3.7)/[0.6/sqrt(32)] = -2.8284
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P(x< 3.4) = P(t<-2.8284 when df = 31] = 0.0041
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Cheers,
Stan H.
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