# Chapter 11 Data Analysis and Statistics - 11.1 Find Measures of Central Tendency and Dispersion - 11.1 Exercises - Skill Practice - Page 747: 13

See below.

#### Work Step by Step

The mean of $n$ numbers is the sum of the numbers divided by $n$. The range is the difference between the largest and the smallest data value. The standard deviation of $x_1,x_2,...,x_n$ is (where $\overline{x}$ is the mean of the data values): $\sqrt{\frac{(x_1-\overline{x})^2+(x_2-\overline{x})^2+...+(x_n-\overline{x})^2}{n}}$. Hence here the mean is: $\frac{3.1+2.7+6.0+5.6+2.3+2.0+1.3 }{7}=3.286$ Hence here the range is: $6-1.3=4.7$, and the standard deviation is: $\sqrt{\frac{(10-3.286)^2+(12-3.286)^2+...+(9-3.286)^2}{7}}\approx1.81$

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.