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    Nicotine confidence interval estimates

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    Refer to Data Set 4 in Appendix B and assume that the samples are simple random samples obtained from normally distributed populations.

    a. Construct a 95% confidence interval estimate of the mean amount of nicotine in cigarettes that are king size, nonfiltered, nonmenthol, and non-light.
    b. Construct a 95% confidence interval estimate of the mean amount of nicotine in cigarettes that are 100 mm, nonfiltered, nonmenthol, and non-light.
    c. Compare the results. Do filters on cigarettes appear to be effective?

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    https://brainmass.com/statistics/statistical-theory/nicotine-confidence-interval-estimates-646128

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    a
    Refer to the Excel spreadsheet for the computations. Computations have been rounded to 3 decimal places.
    Sample size = 25 (there are 25 values in the list)
    Mean = 1.256
    Sample standard deviation = 0.233
    t-value = 2.064
    Margin of Error = 0.096

    Compute the Margin of error by hand using the values above as follows:
    2.064 * 0.233 / ...

    Solution Summary

    Using the Nicotine in cigarettes example, the Excel file contains all formulas and computations: the 95% confidence interval estimates and compares the results. A step-by-step solution is provided.

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