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A sample of 352 subscribers to Wired magazine shows the mean time spent using the Internet is 13.4 hours per week, with a sample standard deviation of 6.8 hours. Find the 95 percent confidence interval for the mean time Wired subscribers spend on the Internet.

  • statistics -

    95% = mean ± 1.96 SEm

    SEm = SD/√n

  • statistics -

    dsva

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