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| Question 1026700:  A random sample of 10 university students was surveyed to determine the amount of time spent weekly at the library. The times are: 13, 14, 5, 6, 8, 10, 7, 12, 15, and 3. If the times are normally distributed with a standard deviation of 5.2 hours, estimate with 90% confidence the mean weekly time at the library by all university students.
 Answer by stanbon(75887)
      (Show Source): 
You can put this solution on YOUR website! A random sample of 10 university students was surveyed to determine the amount of time spent weekly at the library. The times are: 13, 14, 5, 6, 8, 10, 7, 12, 15, and 3.
 Note:: The std of that sample is not 5.2, it is 4.33
 If the times are normally distributed with a standard deviation of 5.2 hours, estimate with 90% confidence the mean weekly time at the library by all university students.
 x-bar = 9.44
 Me = 1.645*5.2/sqrt(10) = 2.7
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 90% CI:: 9.44-2.7 < u < 9.44+2.7
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 cheers,
 Stan H.
 
 
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