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| Question 317029:  Can someone please help me get this problem finished or should I say help me with it. I am totally drawing a blank.
 A randomly selected sample of n = 51 men in Brazil had an average lifespan of 59 years. The standard deviation was 10 years, and the standard error of the mean is 1.400. Calculate a 90% confidence interval for the average lifespan for all men in Brazil.
 1) (56.6, 61.4)
 2)(42.2, 75.8)
 3) (56.2, 61.8)
 Kristal
 
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! A randomly selected sample of n = 51 men in Brazil had an average lifespan of 59 years. The standard deviation was 10 years, and the standard error of the mean is 1.400. Calculate a 90% confidence interval for the average lifespan for all men in Brazil. --------------
 x-bar = 59
 ME = (invT(0.05 with df = 50)*SE
 ME = (1.6759)1.4 = 2.3463
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 90% CI: 59-2.3463 < u < 59+2.3463
 90% CI: 56.65 < u < 61.35
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 Cheers,
 Stan H.
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 1) (56.6, 61.4)
 2)(42.2, 75.8)
 3) (56.2, 61.8)
 Kristal
 
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