Statistics

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The Internal Revenue Service is studying contributions to charity. The mean calculated from a random sample of 36 returns is $150. Assume that the population standard deviation is known and equal to $20. Construct a 98 percent confidence interval for the population mean.

  • Statistics -

    Formula:

    CI98 = mean + or - z (sd/√n)

    mean = 150; sd = 20; n = 36
    Find z using a z-table to represent 98% confidence.

    I'll let you take it from here.

  • Statistics -

    what is answer

  • Statistics -

    The Internal Revenue Service is studying contributions to charity. The mean calculated from a random sample of 36 returns is $150. Assume that the population standard deviation is known and equal to $20. Construct a 98 percent confidence interval for the population mean.

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