# statistics

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Lorraine was in a hurry when she computed a confidence interval for μ. Because σ was not known, she used a Student's t distribution. However, she accidentally used degrees of freedom n instead of n - 1. Will her confidence interval be longer or shorter than one found using the correct degrees of freedom n - 1? Explain.

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Shorter. As the degrees of freedom increase, the value for tc decreases.

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