SOLUTION: 90% of airbags produced by a plant are know to have no defects. Four air bags are tested at random and the number of defective bags are observed.
a) define the random variable
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-> SOLUTION: 90% of airbags produced by a plant are know to have no defects. Four air bags are tested at random and the number of defective bags are observed.
a) define the random variable
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Question 709706: 90% of airbags produced by a plant are know to have no defects. Four air bags are tested at random and the number of defective bags are observed.
a) define the random variable (I put the number of defective bags for this answer)
b) Find the probability distribution for the random variable and construct a histogram (I did a tree diagram but that doesn't take into account the 90% thing)
c) what is the expected number of defective air bags?
d) what is the probability that at most one air bag is defective?
e) What is the probability the first air bag is good and the last three are defective? Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 90% of airbags produced by a plant are know to have no defects. Four air bags are tested at random and the number of defective bags are observed.
a) define the random variable (I put the number of defective bags for this answer)
b) Find the probability distribution for the random variable and construct a histogram
Ans: Binomial distribution with u = np = 4*0.10 = 0.4
and s = sqrt(npq) = sqrt(0.4*0.9) = 0.6
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c) what is the expected number of defective air bags?
u = np = 0.4
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d) what is the probability that at most one air bag is defective
P(at most 1) = P(x = 0)+P(x = 1) = binomcdf(4,0.1,1) = 0.9477
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e) What is the probability the first air bag is good and the last three are defective?
P(gddd) = (0.9)(0.1)^3 = 0.0009
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Cheers,
Stan H.
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