<PRE><B>Question 1051786</B>
From past experience, a company found that in cartons of DVDs, 90% contain no defective DVDs, 5% contain one defective DVD, 3% contain two defective DVDs, and 2% contain three defective DVDs. Find the mean, variance, and standard deviation for the number of defective DVDs. Please explain all steps.
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Percent of defective = 100%-90% = 10%
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mean = n*p = 0.1*n
variance = n*p*q = 0.1n*0.9 = 0.09n
std = sqrt(npq) = sqrt(0.09n) = 0.3*sqrt(n)
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Cheers,
Stan H.
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