Chapter 8.1, Problem 15E

To determine

To find: the confidence level is used and explains the reasoning.

Answer to Problem 15E

80%

Explanation of Solution

Given:

  

Calculation:

  $\begin{array}{c}\frac{21}{25}=0.84\\ =84\%\end{array}$

The red lines under the curve are showing the sample means which is no having the true population mean. It is observed that 4 samples out of 25 which is not having the true proportion and therefore 21 sample of the 25 is having the true mean. The closest confidence level is 80 percent.