Question 1141149: 1. In the most recent election, 19 percent of eligible college students voted. If random sample of 20 students were surveyed, find the probability that none of the students voted?
2. Container 1 has 8 items, 3 of which are defective. Container 2 has 5 items, 2 of which are defective. If one item is drawn from each containger, what is the probabilty that only one of the items is defective
3. Assume the number of trucks passing an intersection has a Poisson disribution with a mean of 5 trucks per minute. What is the probability of 0 or 1 trucks in a minute
4. The life of a light bulb is exponentially distributed with a mean of 1,000 hours. What is the probability that the bulb will last less than 800 hours
5. If n = 15 and p= 4, then the standard deviation fo the binomial distribution is
Answer by Boreal(15235)   (Show Source):
You can put this solution on YOUR website! 1. This would be 0.81^20 for none of the 19=0.0148
2. With a tree diagram, there are two possibilities, one is ND from 1 D from 2, with probability (5/8)(2/5)=(1/4) and the other is (3/8)(3/5)=9/40 That would be 19/40 for the answer.
3. Poisson parameter lambda=5
for P(0), it is e^(-5)(5^0)/0! or e^(-5)=0.0067
for P(1), it is e^(-5)(5^1)/1! or 5e(-5)
The total probability is 6e^-5 or 0.0404
4. the mean is 1000 hours, so lambda is the reciprocal or 1/1000
the probability it will last <800 hours is 1-e^(-800*1/1000) or 1-e^(-.8)=0.5507
5. assume p=0.4 since it ca't be 4
sd is sqrt (np*(1-p))=sqrt (6*0.6=sqrt(3.6)=1.90
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