SOLUTION
Step1; Write out the set of data
7, 13, 8, 3, 11, 7, 14, 7, 18, 2
The mean is given as
![\bar{x}=\frac{\text{SUM OF DATA}}{frequency}](https://img.qammunity.org/2023/formulas/mathematics/college/vhvbcq580d4140x21gp3ari40d8qsgs8nb.png)
![\bar{x}=(2+3+7+7+7+8+11+13+14+18)/(10)=(90)/(10)=9](https://img.qammunity.org/2023/formulas/mathematics/college/m9ribfpehhhvjxwn3ia9mbngzc2y0n3f3g.png)
The mean is 9.00
The variance of a set of data is given as
![\sigma^2=\frac{\sum (x-\bar{x})^2}{n}](https://img.qammunity.org/2023/formulas/mathematics/college/l65yhamw4wf9wrwtubt45fxq0tq5tzr6mj.png)
consider the table below
![\begin{gathered} (\sigma^2=(2-9)^2+(3-9)^2+(7-9)^2+(7-9)^2+(7-9)^2+(8-9)^2+(11-9)^2+(13-9)+(14-9)^2+(18-9)^2)/(10) \\ \end{gathered}]()
Hence the variance becomes
![\sigma^2=(49+36+4+4+4+1+4+16+25+81)/(10)_{}](https://img.qammunity.org/2023/formulas/mathematics/college/jcs5zfszr6fr9z28e39bkia7h3kjmvnyh9.png)
![\sigma^2=(224)/(10)=22.40](https://img.qammunity.org/2023/formulas/mathematics/college/32c9igga3sswcpzexzodgxvy8irdiyvco1.png)
The variance is 22.40
The standard deviation is given as
![\begin{gathered} \text{std}=\sqrt[]{variance} \\ \sigma=\sqrt[]{22.40}=4.73 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/621evz2gc1b995hdwqtzpz4jergjbu6am7.png)