Tiffany N. KeysŐ Essay 1:

Friday the Thirteenth

For Investigation A, I prepared a spreadsheet in Microsoft Excel in order to show that for any year there must be at least one month and at most three months for which the 13th of the month falls on Friday.  I showed this given any day that January 1st could possibly fall on. The month in which the 13th falls on a Friday has been highlighted.

In order to make comparisons between leap years and non-leap years in Investigation B, I prepared two spreadsheets in Excel in order to show which months have Friday the 13th in them.  Like Investigation A, I showed this for any given day in which January 1st could fall on in non-leap years and leap years.

1.    I researched that January 1st occurred on a Thursday therefore resulting in a Friday the 13th in both February and March.  From the spreadsheet I prepared, I can confirm that Thursday is the only day in which January 1st could fall in a non-leap and leap year in which results in two consecutive Friday the 13th in February and March.

2.   The next year in which there will be two consecutive Friday the 13th in February and March will be in 2009.  Since January 1, 2009 will occur on Thursday, my spreadsheet confirms this.

3.    I do not think that there is a pattern or cycle for which I can determine which years between 2000 and 2100 there will be two consecutive Friday the 13th in February and March because the day in which the first day of the year occurs appears to be the determining factor for this event.  There probably is a pattern or cycle for which one can determine what day January 1st will fall on.