We have to calculate the mean of the given dataset.
We can do it with the expression:
![\bar{x}=(1)/(n)\sum_(i=1)^nx_i](https://img.qammunity.org/2023/formulas/mathematics/college/28zsuwpzd1rbgg67xa1ybb8pribof574g1.png)
where n is the size of the dataset and xi is the value of each of the elements of the data set.
We can then calculate the mean as:
![\begin{gathered} \bar{x}=(1)/(15)(8+12+15+9+10+12+12+18+14+15+10+11+12+9+17) \\ \\ \bar{x}=(1)/(15)(184) \\ \\ \bar{x}\approx12.3 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/1q1be667uohnizwl5xufmgpynkplrtys2f.png)
Answer: the mean of this dataset is 12.3.