Explore BrainMass

Explore BrainMass

    Statistics: Develop Confidence Interval

    This content was COPIED from BrainMass.com - View the original, and get the already-completed solution here!

    Families USA, a monthly magazine that discusses issues related to health and health
    costs, surveyed 20 of its subscribers. It found that the annual health insurance premiums
    for a family with coverage through an employer averaged $10,979. The standard deviation
    of the sample was $1,000.

    a. Based on this sample information, develop a 90 percent confidence interval for the
    population mean yearly premium.
    b. How large a sample is needed to find the population mean within $250 at 99 percent
    confidence?

    © BrainMass Inc. brainmass.com June 3, 2020, 11:31 pm ad1c9bdddf
    https://brainmass.com/statistics/confidence-interval/statistics-develop-confidence-interval-283308

    Solution Summary

    A Complete, Neat and Step-by-step Solution is provided in the attached Excel file.

    $2.19

    ADVERTISEMENT