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| Question 314741:  I have been working on my homework all day and this may be the simplest of problems but I am confusing myself and I was wondering if I could get a little help figuring it out. Can you show me how you get the answer.
 Suppose on a highway with a speed limit of 65 mph, the speed of cars are independent and normally distributed with an average speed = 65 mph and standard deviation = 5 mph. What is the expected value of the sample mean speed in a random sample of n = 100 cars?
 A) 13 mph
 B) 0.65 mph
 C) 6.5 mph
 D) 65 mph
 Thanks,
 Dave
 
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! Suppose on a highway with a speed limit of 65 mph, the speed of cars are independent and normally distributed with an average speed = 65 mph and standard deviation = 5 mph. --------------------------
 What is the expected value of the sample mean speed in a random sample of
 n = 100 cars?
 -----------------------
 The distribution of ALL samples of size
 100 has a mean of 65 and std=5/sqrt(100).
 ----
 Expected value of the sample mean speed = 65 mph.
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 Cheers,
 Stan H.
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 A) 13 mph
 B) 0.65 mph
 C) 6.5 mph
 D) 65 mph
 
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