Mean: We add them all and divide by the number of them: [tex] \frac{89+81+77+77+89+91}{6} [/tex] = 84
Median: We put them in order and take halfway inbetween the two middle values: 77, 77, 81, 89, 89, 91. [tex] \frac{81+89}{2} [/tex] = 85
Mode: We find the most common value. In this case both 77 and 89 appear twice, so 77 and 89.
