One way that I determine the weekday of a particular date is to enter the date into a cell in a Microsoft Excel spreadsheet and to format the cell to show the weekday. For dates before 1 January 1900 I add a multiple of 400 to the year to make the year greater than 1899 (the Gregorian calendar completely repeats itself every 400 years).
The other way is to look at the year in the perpetual calendar I created for myself.
October 27th, 1972 was a Friday.
October 25th 1972 was a Wednesday.
13 October 1972 was a Friday.
10 October 1972 was a Tuesday.
October 1 1972 was a Sunday.
October 25, 1972 fell on a Wednesday.
October 12, 1972 fell on a Thursday.
October 13, 1972 fell on a Friday.
October 20, 1972 fell on a Friday.
October 16th, 1972 fell on a Monday.
October 30, 1972 fell on a Monday.
Sunday