Friday, 26 August 2011

DAY 356

How many 5th Sundays are there in a year? (Ignore the possibility of 53 Sundays.)

Answer:
4 ......... There are 52 Sundays in a year. Each month has at least four, which is 48. The remaining 4 are fifth Sundays.

NOTE from JA: 
September 3, 2016 

I have been thinking about this problem for some time. The above statement about 48 Sundays is also true of every other day of the week. So 48 x 7 = 336. This leaves 29 more days (365-336). 29 divided by 7 = 4 remainder 1. This means there are 4 fifth Mondays, Tuesdays, Wednesdays, Thursdays, Fridays, and Saturdays - as well as 4 fifth Sundays. What about the extra day? It must mean that every year has one day that occurs 53 times - cycling through the week every seven years.

1 comment:

  1. Good answer, but you're forgetting leap years. Meaning every 4th year (excluding every 100th year - except if that 100th year is divisible by 4) there are 2 days of the week that get an extra day in the year.

    ReplyDelete