The Marketing Manager of a Pizza Chain Is in the Process

The marketing manager of a pizza chain is in the process of examining some of the demographic characteristics of her customers. In particular, she would like to investigate the belief that the ages of the customers of pizza parlours, hamburger emporiums and fast-food chicken restaurants are different. As an experiment, the ages of eight customers of each of the restaurants are recorded and listed below. From previous analysis we know that the ages are not normally distributed. $\begin{array} { | c | c | c | } \hline & { \text { Custoner Age } } \\\hline \text { Pizza } & \text { Hamburger } & \text { Chicken } \\\hline 23 & 26 & 25 \\\hline 19 & 20 & 28 \\\hline 25 & 18 & 36 \\\hline 17 & 35 & 23 \\\hline 36 & 33 & 39 \\\hline 25 & 25 & 27 \\\hline 28 & 19 & 38 \\\hline 31 & 17 & 31 \\\hline\end{array}$ Do these data provide enough evidence at the 10% significance level to infer that there are differences in age among the customers of the three restaurants?