SOLUTION: According to police sources, a car with a certain protection system will be recovered 94% of the time. If 400 stolen cars are randomly selected, what is the mean and standard devia

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Question 888644: According to police sources, a car with a certain protection system will be recovered 94% of the time. If 400 stolen cars are randomly selected, what is the mean and standard deviation of the number of cars recovered after being stolen?
Answer by Okamiden(22) About Me  (Show Source):
You can put this solution on YOUR website!
This is a Binomial distribution with p=0.94 and n=400. The standard deviation will thus be ++sqrt%28n%2Ap%2A%281-p%29%29=+sqrt%28400%2A0.94%2A0.06%29+=+4.75++ approximately. It's a direct application of the formula, with the tricky part being that you must recognize that this is a binomial distribution.
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The mean is simply 0.94*400 = 376. :)