Autumn Color

 

In my 'Bathroom Brain Teaser' book (don't ask) it said "On September 9, 1981 the product of the month times the day equals the last two digits of the year - i.e. 9x9=81.  When is the next time this happened?"  I mentally answered (after some thought) March 28, 1984 - i.e. 3x28=84.  The answer in the book was "January 1, 2001 - i.e. 1x1=01".  Well that made no sense.  Even if I was wrong on picking the very next date, there are plenty of other dates before 2001 where the number of the month times the number of the day equals the last two digits of the year.  Finally figured out what they were trying to ask  was not that the product of the month and the day but the square root of the month or the day.  For that the month and the day have to be the same number.  The next time that happens will be May 5, 2025.   No need to try and remember the day.  I'm sure the Internet will be full of warnings of the dire things that will happen when the year is the square root of the month and day.  Am more concerned that I'm apparently smarter than my Brain Teaser book.