# 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.

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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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