## Elementary Statistics (12th Edition)

The mean can be counted by summing all the data and dividing it by the number of data: for white drivers: $\frac{74+77+69+71+77+69+72+75+74+72}{10}=73$, for African American drivers: $\frac{79+70+71+76+76+74+71+75+74+74}{10}=74$. The median is the average of the 1 or 2 (here 2) middle data: for white drivers:(74+72)/2=73, for African American drivers:(74+74)/2=74. The African American drivers appear to speed more because their mean is more.