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Solve: 99% Confidence Interval

7. The random sample shown below was selected from a normal distribution.

8, 3, 6, 10, 6, 3

Complete parts a and b.

Construct a 99% confidence interval for the population mean. Round to two decimal places as needed. Assume that the sample mean and sample standard deviation remains exactly the same as those you just calculated, but that are based on a sample of n = 25 observations. Repeat part a. What is the effect of increasing the sample size on the width of the confidence intervals? Round to two decimal places.

What is the effect of the sample size on the width of the confidence interval?

Select the best answer below:
As the sample size increases, the width stays the same.
As the sample size increases, the width decreases
As the sample size increases, the width increases

Solution Preview

Hi there,

Thanks for letting me work on your post. I've included my explanation in the word document.

7. The random sample shown below was selected from a normal distribution.
8, 3, 6, 10, 6, 3
Complete parts a and b.

Construct a 99% confidence interval for the population mean μ. Round to two decimal places as needed.
The mean: (8+3+6+10+6+3)/6=6
Standard deviation: ...

Solution Summary

A random sample is analyzed by using 95% confidence intervals. The population mean is constructed.

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