Question

The data in Table are the result of a random survey of $39$national flags (with replacement between picks) from various countries. We are interested in finding a confidence interval for the true mean number of colors on a national flag. Let $X=$the number of colors on a national flag.

$\begin{array}{|cc|}\hline \mathit{X}& \text{Freq.}\\ 1& 1\\ 2& 7\\ 3& 18\\ 4& 7\\ 5& 6\\ \hline\end{array}$

Is ${\sigma }_x$known.

Short answer

${\sigma }_x$is unknown.

Step-by-step solution

Given Information

The data in the Table are the result of a random survey of $39$ national flags (with replacement between picks) from various countries.

$\begin{array}{|cc|}\hline \mathit{X}& \text{Freq.}\\ 1& 1\\ 2& 7\\ 3& 18\\ 4& 7\\ 5& 6\\ \hline\end{array}$

$\begin{array}{|cc|}\hline \mathit{X}& \text{Freq.}\\ 1& 1\\ 2& 7\\ 3& 18\\ 4& 7\\ 5& 6\\ \hline\end{array}$

Explanation

Apart from the mode and median, the mean is one of the measures of central tendency used in statistics. The average of a group of values is known as the mean. It refers to a data set's values being distributed evenly.