## Essentials of Statistics (5th Edition)

The mean can be counted by summing all the data and dividing it by the number of data: Brinks as collection contractor: $\frac{1.3+1.5+1.3+1.5+1.4+1.7+1.8+1.7+1.7+1.6}{10}=1.55$, not Brinks as collection contractor: $\frac{2.2+1.9+1.5+1.6+1.5+1.7+1.9+1.6+1.6+1.8}{10}=1.73$. The median is the average of the 1 or 2 (here 2) middle data: Brinks as collection contractor:(1.5+1.6)/2=1.55, not Brinks as collection contractor:(1.6+1.7)/2=1.65. It does not show evidence because the mean of Brinks employees is less than the mean of not Brink employees.