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A random sample of 42 college graduates revealed that they worked an average of 5.5 years on the job before being promoted. The sample standard deviation was 1.1 years. Using the .99 degree of confidence, what is the confidence interval for the population mean? 

  • Math -

    99% = mean ± 2.54SD = ?

  • Math -

    5.06 and 5.94

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