## Essentials of Statistics (5th Edition)

The mean can be counted by summing all the data and dividing it by the number of data: $\frac{78+81+95+73+69+79+92+73+90+97}{10}=82.7$, the mean is 82.7. The mode is the data occurring the most times and here the mode is 73, which appears twice. The median is the average of the 1 or 2 (here 2) middle data: (81+79)/2=80, the median is 80. The mid range is the average of the highest and the lowest data: (69+97)/2=83, the mid range is 83. We do not know which death rate belongs to which year.