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Chapter 8: Q 15. (page 507)

How confident? The figure shows the result of taking 25SRSs from a Normal population and constructing a confidence interval for the population mean using each sample. Which confidence level—role="math" localid="1654197644211" 80%,90%,95%,or99%—do you think was used? Explain your reasoning.

Short Answer

Expert verified

Confidence Level of80%is used.

Step by step solution

01

Given Information

It is given that:

02

Determining Confidence Level

Calculating Confidence Level

2125=0.84

84%

Red line implies those sample means which have no true population mean.

Hence, 4samples out of 25don't have true population. So, 21sample have true mean.

Closest Confidence Level is80%.

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