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—80%,90%,95%,or99%—do you think was used? Explain your reasoning.

Short Answer

Expert verified

Confidence Level of99%is used.

Step by step solution

01

Given Information

We are given that

02

Determining Confidence Level Used

Confidence Level is calculated as 2525=1

100%

  • Red line implies those sample means which have no true population mean.
  • There are zero samples among given 25samples not containing true proportion.
  • Hence, 25samples from 25samples has true population.
  • The confidence level which is closest is99%

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