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A professor found that historically, the scores on the final exam tend to follow a normal...

A professor found that historically, the scores on the final exam tend to follow a normal distribution.  A random sample of nine test scores from the current class had a mean score of 187.9 points and a sample standard deviation of 32.4 points. Find the 90% confidence interval for the population mean score of the current class.

  • A.

    [167.81, 207.99]

  • B.

    [ 170.13 , 205.67]

  • C.

    [ 166.73, 209.07]

  • D.

    None of these answers are correct.

Math   Statistics-And-Probability   
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