In the Western Gregorian Calendar, the date of Easter Sunday is defined as the Sunday following the ecclesiastical Full Moon that falls on or next after March 21. While the pattern of dates so defined usually repeats each 19 years, there is a 0.08 day difference between the cycles. More accurately, the system has a period of 70 499 183 lunations…

Presents an activity in which students use computer-based spreadsheets to find out how much grain should be added to a chess board when a grain of rice is put on the first square, the amount is doubled for the next square, and the chess board is covered. (ASK)