1. Begin with a pile of pennies. How many does your group have?
2. Line up the pennies in the order of their dates, from earliest to the most recent. If more than one are dated the same, stack them. Determine the mode by finding the highest stack of pennies (Mode, for those of you who forgot - or never knew - means which number in the list appears the most often. Mode means most.).
3. Find the range by subtracting the earliest date from the latest (Range is the difference between the highest and lowest numbers in the list.).
4. Next, unstack the like-dated pennies and add them to the line. Stretch the line out to accommodate them. Now figure out which penny is in the very center (We began with 51 for each group). The center penny displays the median date.
5. Pick up a calculator and pay close attention to the buttons you push to find the mean. Add every date on every penny to find the sum, and divide by the number of pennies in your line.