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    Confidence Interval; Margin of Error

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    (1) The confidence interval: 5.06 < sigma2 < 23.33 is for the population variance based on the following sample statistics:

    n = 25, x-bar = 41.2, and s = 3.1

    What is the degree of confidence? Use only integers, no % sign and no decimal places.

    (2) Find the margin of error.

    95% confidence interval; n = 91 ; x-bar = 55, s = 5.4

    Round to the nearest two decimal places.

    See attached file for full problem description.

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    13.
    The confidence interval: 5.06 < sigma2 < 23.33 is for the population variance based on the following sample statistics:
    n = 25, x-bar = 41.2, and s = 3.1

    What is the degree of confidence? Use only integers, no % sign and no decimal places.
    (Points: 3)

    The confidence interval for a population variance is calculated as:

    (n - 1)s2 &#8804; &#963;2 &#8804; (n - 1)s2
    X2&#945;/2, n - 1 X21- &#945;/2, n - 1

    The X2&#945;/2, n - 1 and the X21- &#945;/2, n - 1 are critical values from the chi-squared distribution. We'll find them in a minute.

    From the problem, we know that the left side of the inequality is equal to 5.06 and the ...

    $2.19

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