The data below are the seventeen shoe sizes of one type of shoe sold in one day at a local shoe store.

DATA: { 5, 6, 7, 7, 7, 7, 7, 7, 8, 9, 9, 10, 11, 12, 13, 13, 15 }

Mean: 9

Median: 8

Mode: 7

Given the way the data is distributed in this example (with so many size seven shoes being sold), the mode is probably the best measure of central tendency.