Problem

For the provided sample mean, sample size, and population standard deviation, complete parts (a) through (c) Assume that x is normally distributed.
x¯=29,n=9,σ=6
a. Find a 95% confidence interval for the population mean

The 95% confidence interval is from 25.08 to 32.92 .
(Round to two decimal places as needed.)
b. Identify and interpret the margin of error.

The margin of error is .
(Round to two decimal places as needed.)

Answer

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Answer

The final answer is: The 95% confidence interval for the population mean is from 25.08 to 32.92. The margin of error is 3.92.

Steps

Step 1 :Given the sample mean x¯=29, sample size n=9, and population standard deviation σ=6.

Step 2 :Calculate the standard error (SE) using the formula σ/n, which gives SE = 2.0.

Step 3 :Find the z-score for a 95% confidence level, which is z=1.96.

Step 4 :Calculate the lower and upper bounds of the confidence interval using the formulas x¯z×SE and x¯+z×SE, respectively. This gives a confidence interval from 25.08 to 32.92.

Step 5 :Calculate the margin of error (ME) using the formula z×SE, which gives ME = 3.92.

Step 6 :The final answer is: The 95% confidence interval for the population mean is from 25.08 to 32.92. The margin of error is 3.92.

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